Hurricane Season Wrap-Up

Finally, a news story to remind us about the huge clean-up problems still remaining from hurricanes Dolly, Gustav, and Ike. Lots of questions, no easy answers. Certainly it was another rough year for Texas (not to mention Cuba).

A High Tide in a Low City

Residents of Venice, Italy dealt with widespread flooding from the sea yesterday. Strong winds helped to raise the sea to its highest level since 1986. Although parts of the city are perennially submerged and served by water buses and gondolas, the rise of waters to about 5 feet above normal exceeded the limits of the city's transportation system and put almost all of the city's streets under water. As the normal astronomical low tide set in later in the day, conditions rapidly returned to normal and clean-up began.

The Storms After the Election

After a period of mostly moderate weather across the country, today we have a late-season hurricane (not expected to impact the United States) and a strong mid-latitude cyclone.

In the wake of the occluded low in Minnesota, much of the northern Plains has had to deal with blizzard conditions. In western South Dakota, snow accumulation has exceeded 4 feet and up to 20 foot drifts have been reported. At one point, peak winds exceeded 70 mph.


Down in the Caribbean, Hurricane Paloma has reached Category 2 strength and is moving northeast towards Cuba. The immediate threat however is for the Cayman Islands. After passing over Cuba during the weekend, the weakened storm is expected to proceed through the islands of the Bahamas, with little chance of a significant impact on South Florida.

National Weather Association Meeting

Just got back from the annual meeting of the National Weather Association (NWA) in Louisville, KY. Unlike the American Meteorological Service, the NWA emphasizes operational meteorology, particularly for National Weather Service forecasters. So it's a different crowd and the conference presentations are much more commonly dealing with recent and historical case studies rather than purely theoretical studies.

One complete session this year was focused on the tornado and severe storm outbreak that occurred on February 5-6 of this year, during the Super Tuesday primary election. Some noteworthy talks on tools for operational meteorology included: "High Resolution, Lower Tropospheric Radar Networks: The CASA Program" by Brenda Phillips et al.; "Using Google Earth as a Situational Awareness Tool: An NWS Central Region Headquarters Example" by Brian Walawender; and "GR Level 2 Analyst" by Mike Gibson. Some other talks that I especially enjoyed were: "The Columbus Day Windstorm of 1962" (Wikipedia) by Brad Coleman; "Wintertime Mesoscale Vortices over Lake Michigan" by Sam Lashley; and "Forecasting Cold Air Damming and the Position of the Wedge Front over Northern Georgia" by Patricia Atwell et al.

Interesting poster presentations included: "Analysis of an Undular Bore over the Gulf of Mexico on March 15, 2008" by Roger Erickson; "West Texas Mesonet Proximity Observations for Wind-Driven Wildfire Starts" by Jeffrey Vitale and T. Todd Lindley; "Point Verification of Acceptable Temperature Forecasts Across the NWS Southern Region" by Bernard Meisner and Mark Fox; and "Case Study of the 3 February 2008 Valdez Bora Wind Event" by Louise Fode and James Nelson.

Omar Va Por El Mar

After its rapid intensification over the last couple days, Hurricane Omar has skirted Puerto Rico and the Virgin Islands. Now it will continue to accelerate northeastward into the middle of the Atlantic Ocean. Winds have already decreased from a peak of 125 mph to only 70 mph.

Speaking of hurricanes, recent preoccupation with the economic crisis and presidential election has taken hurricane recovery in Texas and Louisiana out of the spotlight even faster than usual. Nevertheless, challenges still remain for many whose homes were damaged by Gustav and Ike.

East Coast Storms

A low pressure area that developed along a weakening cold front has intensified substantially over the warm waters of the Gulf Stream. Although surface winds are strong enough to be a tropical storm, the system does not really appear to be "tropical", at least not at this point. Current satellite imagery reveals a structure more similar to a "subtropical storm". There is a tight circulation of cloud bands, but not continuous convection in all quadrants or concentrated near the center. It also has some characteristics of an early fall "nor'easter".



Tropical storms are primarily driven by latent heat release from an inner core of thunderstorms with a broad area of outflow above the low. This deep warm core of rising motion is related to the relatively small area of intense low pressure at the surface. In contrast to most extratropical (i.e. not tropical) cyclones, thermal wind arguments imply that the strongest winds in a tropical cyclone will be near the surface rather than near the tropopause. With the current system, the center does not appear to be very convectively unstable and it looks like it will take on a more extratropical character over the next couple days. In any case, it will bring some messy conditions along much of the Eastern Seaboard, but probably no reason for hysteria. There is also a good discussion on Jeff Masters' Wunder Blog.

Another area of interest, to the east of the Bahamas, is definitely tropical and may have some potential for development. But it's relatively unlikely to impact the United States.

First Day of Fall . . . or Spring?

It was a nice first day of fall across most of the United States today. But in the Southern Hemisphere it's the first day of spring. In some of the higher elevations of South Africa that meant a surprise snow storm that has caused problems for traffic in the KwaZulu-Natal and Eastern Cape areas.

Monsoon Flooding in West Texas?

The extensive rains across northern Mexico and West Texas from the retreating North American monsoon are bringing historic flooding to the Rio Conchos and Rio Grande. As reservoirs on the Rio Conchos overflow, the downstream cities of Ojinaga (in Chihuahua, Mexico) and Presidio (in Texas) have watched flood waters breach their levees. The deaths of the U.S. and Mexican directors of the International Boundary Waters Commission and Rio Grande Council of Governments in a plane crash while surveying the flood have added to the tragedy.

The Long Reach of Ike

While news coverage of the devastation from Hurricane Ike has somewhat been in competition with election and financial news, and the problems are less dramatized than with Katrina, it's important to consider how broad a swath of the country has been impacted by this storm. While Hurricane Katrina effectively wiped out infrastructure from southern Louisiana to central Mississippi, the rapid movement of Ike brought major problems all the way up to the Canadian border. This is shown dramatically by the 24 hour radar-estimated precipitation through Sunday morning.



The combination of flooding and high winds have left millions of people homeless or without power as far away as western Pennsylvania! On the other side of Ike's (fourth!) landfall, the rebuilding process is challenging the residents of Grand Turk, Inagua, Haiti, eastern Cuba, and western Cuba. The wipeout of Galveston should be compared to the destruction that Grand Turk has sustained from when the hurricane was still a Category 4 on the Saffir-Simpson scale, or the misery of Gonaives, Haiti after being inundated by four tropical cyclones in a row.

A Tropical Plume

The big news story lately has of course been Hurricane Ike. However there was also an interesting situation further to the west, before the landfall of Ike. From northern Mexico up into West Texas and Oklahoma, there was a persistent swath of cloud cover and rain. In spite of some analyses, this was not primarily due to interaction with a frontal zone. Instead, it was due to a plume of mid-level tropical moisture being blown northeastwards from Tropical Storm Lowell in the Pacific. In terms of winds or direct impacts, Lowell was never much of a storm. But its remote impacts through this plume of moisture were fairly significant. To some extent this pattern simply extended the influence of the North American Monsoon System further east into the Plains than usual. Because of the relatively wet ground in northern Mexico, it was feared that there could have been particularly bad flash flooding if Ike had tracked to the west over the region. The area of East Texas that was traversed by Ike was actually somewhat in need of rain, although they obviously could have done without the high winds.

Between Storms?

A preliminary description of impacts of Gustav on the Ark-La-Miss region is now available. Many homes in Louisiana and Mississippi remain without power. Now all eyes are on Hurricane Ike, with its 135 mph winds and a forecast that takes it over the Turks & Caicos Islands, the southern Bahamas, Cuba, and then into the Gulf of Mexico.



In central Mississippi, Saturday turned out remarkably cool and fall-like. In spite of official forecasts for a high in the low 90s that were revised to 86, the mercury actually struggled to even reach 80 under a light north breeze.

More on the Way and Some Change in the Air

As people return to south Louisiana and Mississippi, they're finding a mess and a long wait for power restoration, and have been largely forgotten by the media. Meanwhile the tropics continue to cook up more storms. Tropical Storm Hannah may have struggled and appear relatively wimpy, but it's unwelcome excursion southward brought another onslaught of misery to northern Haiti. While it was stuck in an area of with no significant upper-level steering currents, it made an unusual cyclonic loop.


Further out, we have Ike and Josephine. In all probability, Josephine will be a "fish" storm that just spins around in the open ocean, and is not expected to intensify significantly anyway. Ike is another matter. After a dramatic period of intensification yesterday, it is expected to enter the less favorable environment that Hannah has struggled in. It will probably approach the Florida as a significant hurricane, but hopefully no longer as a Category 4 storm.

Meanwhile, central Mississippi had a bit of a change today. Not only did the sun finally come out for a while, but the first weak cold front of the fall pushed through. It's always nice to have dewpoints drop from the mid-70s to the mid-60s. Of course, the reality is that it won't last very long.

Hurricane Party or Gas War?

On the third anniversary of Hurricane Katrina, Mississippi and Louisiana are trying to figure out an eerily familiar scenario. Although Fay pretty well fizzled before it could have much of an impact on central Mississippi, Gustav seems poised to provide a more credible threat to the region, especially for Louisiana. Even though Gustav is currently only forecast to become a Category 2 hurricane, many people are not wanting to take chances. Though the forecast landfall is still five days away and Jackson is three hours from the coast, it's amazing to see the social transformation of hurricane preparedness. People are saying that many stores are already out of bottled water and other common preparedness items. Long, long lines at gas pumps this morning have diminished now that prices have shot up by 20 or 30 cents per gallon and several gas stations have run out of supply.

From a scientific standpoint, it looks like we'll end up with three storms (Fay, Gustav, and Hannah) in a row exhibiting unusual (for the region) tracks with southerly wobbles.
And, at this rate, it looks like pretty much every stretch of coastline from Puerto Rico to Houston is liable to be impacted by a tropical cyclone this year!

A Statehouse Scramble

Even politicians have to duck for cover from tornadoes this spring up in Illinois.

Annual Congress of CMOS

Throughout this week the Canadian Meteorological and Oceanographic Society (CMOS) is meeting for its annual scientific Congress at Kelowna, British Columbia. This year's theme is "Water, Weather, Climate: Science Informing Decisions".

DoWaC is back?

Crews fighting a wildfire in the Santa Cruz Mountains of central California are receiving help from more humid weather.

More storms caused damage in rural areas of Oklahoma.

Virginia tornadoes

Yesterday a series of at least three tornadoes tore through southeastern Virginia, with the largest impact being in Suffolk.

Interestingly, yesterday was also the six year anniversary of the catastrophic La Plata, MD tornado. Although tornadoes are not exactly rare in the mid-Atlantic states, an F4 tornado like La Plata had is extremely rare along the Atlantic coast or so far north. The tornado was one of an outbreak of 48 confirmed tornadoes over several states on April 27-28, 2002. The National Weather Service has produced a special assessment report, in addition to a web page created by the local forecast office. More photos are available on this page.

Wind Roses

No, they are not flowers that grow in windy places. A wind rose is the most common way to display statistical information about the relationship between wind speed and direction at a particular site. Basically the frequency of occurrence of winds from different directions is calculated from a dataset, and then a polar plot is constructed (similar to a bar graph) with length out from the center proportional to relative frequency. This allows a simple visual portrayal of the most common (or rare) wind directions. Just remember that meteorological convention always designates wind direction according to the direction that the wind comes from. Within each of the resulting "pie slices" of the wind rose, the relative frequency of different wind speeds may be indicated by areas of different color, similar to a "stacked" bar chart.

Wind roses are used in many applications, such as wind energy development, sailing, and air quality management.

Here is an example of a wind rose showing the winds observed at Miscou Island, New Brunswick, Canada during June 2007:



Software for creating wind roses from raw data files is available from Lakes Environmental (free) and EnviroWare. Precalculated wind roses for many U.S. stations are available online through the Natural Resources Conservations Service. More discussion and examples are available here.

Science fair projects

For students wanting to do science fair or class projects relating to the weather, there are many possibilities. Some of the most interesting however are ones that make use of actual observed weather data. The Oklahoma Climatological Survey maintains a website that lists some sample projects that have been done using data from the Oklahoma Mesonet observing network, as well as several related pages dealing with K-12 education and science fairs.

Several online data sources are listed on the Synoptic Meteorology class webpage, with wunderground.com and the NOAA weather server probably being the most user-friendly.

The Dryline

Especially in the springtime, it's common for a well-developed "dryline" to be found in West Texas. Similar to a front, the dryline is a discontinuity that separates the hot, dry (continental Tropical; cT) air of the Desert Southwest and Mexican Plateau from the warm, moist (maritime Tropical; mT) air that flows off of the Gulf of Mexico. Typically the sudden transition occurs in the vicinity of the 50°F isodrosotherm (line of constant dewpoint temperature). Whether it stays quasistationary or progresses eastward in advance of a low pressure system and cold front, the dryline holds special interest for tornado chasers and other people interested in severe storms since the area northeast of the dryline is often very favorable for initiation of severe convective storms. More than any other atmospheric feature, this is responsible for the existence of "Tornado Alley" in North Texas and central Oklahoma. The presence of dry air contributes to the generally greater visibility of tornadoes compared to tornadoes in the eastern U.S.

This afternoon there is a well-defined dryline extending as far north as western Kansas, with dewpoints in the mT air mass typically between 65-70°F and dewpoints of 10-40°F in most of the cT air mass. Although temperatures to the west of the dryline are generally warmer in the 20 Z observations, this is primarily a reflection of a larger diurnal cycle of temperature in the drier air. In early morning, the temperature gradient will often be reversed from the afternoon pattern. The dewpoint discontinuity is often maintained and strengthened by converging surface winds within a weak lee/thermal trough. When a dryline intersects a cold front, the point where they meet is commonly referred to as the triple point.

Weather Modification?

So is there actually any way that we can change the weather? While it's become increasingly well established that human activity can cause systematic climatic changes by modifying the land surface and contributing air pollution, such unintentional effects normally seem to make things worse instead of better. Of course, for every loser there's usually a winner. For example, if a drought causes crop failures in one area, then farmers in other areas may reap profits from higher prices.

The two applications that people usually think of for intentional weather modification are increasing rain over dry areas and minimizing the impact of hurricanes. Science-based rain-making has been attempted since at least the 1940s, although only fairly recently have researchers been able to show a clear improvement, under ideal circumstances. Known as cloud seeding, this normally involves injection of silver iodide or other specialized salts to help cloud droplets grow faster. Currently the big news is how much money China has invested to try to produce favorable weather for the Beijing Olympics. In general their effort is viewed with substantial skepticism.

Attempts to modify the strength or path of hurricanes have largely either been dismal failures or figments in the imagination of conspiracy theorists. For several years, the U.S. government supported research on Project StormFury, before determining that the potential for useful modification was exceeded by the inherent risks. Although federal research funding for hurricane modification has dried up, new (and old) ideas continue to be proposed. These have included moisture-absorbing gels, atomic bombs, and oil slicks.

Other areas of interest in weather modification are hail suppression (e.g. in Alberta) and clearing fog at airports.

A Big Flood on the Lower Mississippi

The current flooding along the lower Mississippi River has reached historic levels, bringing back memories of 1927, 1973, and other major flood years. So far the levees have held back major disaster though. Within the state of Mississippi, the river has now crested, barring any rises due to additional rainfall upstream. Estimates are that a couple hundred homes have been impacted. With about half of the floodgates on the Bonnet Carre Spillway now open above New Orleans, the huge amount of river water flowing into Lake Pontchartrain is now giving concerns that small boats may collide with floating debris entering the lake.

In the Mississippi Delta area to the east of the big river above Vicksburg, the current flooding has heightened the debate about a Corps of Engineers pumping scheme that appears headed for a veto by the Environmental Protection Agency (EPA).

The Father of Chaos

Yesterday Dr. Edward Lorenz died of cancer at age 90. He was a respected meteorology professor at MIT, who was the first to significantly develop chaos theory and apply it to the atmosphere. Out of that came our current concepts of atmospheric predictability and the need for ensemble methods in numerical forecasting.

Some outdoor recreation weather dangers

In New Zealand, six college students and their instructor drowned on Tuesday in a flash flood while hiking in the Mangetepopo Gorge.

Climbers in Scotland are concerned about the seasonal ending of the avalanche forecasting service while large amounts of snow remain on the mountains. Up in Juneau, Alaska, the problem is a major avalanche that knocked out transmission lines supplying power to the city.

Thunderstorms and Snow

Although the thunderstorms that rumbled through the South today were tame in comparison to last week's batch, the large storm system dominating the middle of the country still caused some problems. In particular, Minnesota was subjected to blizzard conditions that shut down mail delivery in some areas.



Other areas dealing with late season snow included Calgary, Alberta and even all the way down to western Kansas. And then there are the extreme seasonal snowfall totals that have accumulated, such as in Spokane, WA, Vail, CO, and Concord, VT.

High Water on the Big Muddy

With levels continuing to rise on the lower Mississippi River, the most extensive river flooding in11 years is now developing. Although the probable opening of the Bonnet Carré Spillway would give protection for New Orleans, other river towns are beginning to feel the impact. The Corps of Engineers has heightened monitoring of levees, and there has been a breached private levee today in the area of the Morganza Spillway.

Mississippi Cleaning Up

The cleanup from Friday's storms in Jackson and central Mississippi continues, and will for a while.

Initial storm reports are now available from the National Weather Service.

A Stormy Day in the South

Last night Little Rock, Arkansas had major damage from a tornado.

Today the squall lines marched across Mississippi. All of this stormyness was in the warm moist air a few hundred miles ahead of a cold front. Even at 12Z (7:00 AM) this morning, the upper air soundings were showing unstable air across the region, with CAPE of 666 J/kg at Jackson and 1375 at Shreveport (which was already near the squall line). The severe winds of the squall line came through the Jackson Metro area around 12:30 this afternoon, resulting in widespread damage. The ASOS at Hawkins Field in Jackson recorded the following report of 47 kt wind gusts before apparently losing power:

KHKS 041729Z 28035G47KT 1 1/4SM HZ SQ FEW036 BKN046 BKN070 24/17 A2994 RMK AO2 PK WND 26047/1728 PRESRR P0002

Earlier this morning, the surface charts provided a good example of potential problems in frontal analysis due to squall lines, outflow boundaries, and rain-cooled air.


For the most part, the fronts and air masses are easily identified in the RUC Theta-e analysis, including the relict cool air mass to the east of the Appalachians. The important point to note is that the low Theta-e air mass extending from northern Louisiana to Ohio is due to low-level rain-cooled air behind the squall line.
In east-central Texas the visible satellite imagery showed a dramatic shadow from the anvil of a complex of severe storms. Overshooting tops were also fairly pronounced in the morning sunlight.



Here is the radar reflectivity showing the squall line approaching Jackson:


And a close-up of the Doppler velocity just before the strongest winds reached JSU, showing storm-relative winds in excess of 50 kt:

Weather Roundup

Strong winds associated with a southerly buster (cold front) caused widespread damage in much of Australia. There was a dramatic rescue from the snow in Keswick Ridge, New Brunswick (Canada). And snow removal costs in northern Maine have prompted calls for federal disaster declarations.

NOAA Air Resources Lab

NOAA's Air Resources Lab (ARL) is the primary NOAA branch dealing with research on air quality and chemistry issues. Offices are located in Maryland, Tennessee, Idaho, North Carolina, and Nevada. Particular emphasis in recent years has been on urban meteorology and applications for homeland security. In recent years, JSU has worked with ARL on atmospheric dispersion studies and data collection, in concert with the UrbaNet project. Another prominent project of ARL has been the East Tennessee Ozone Study (ETOS). The NOAA/ATTD DataViewer is an effort to dynamically mesh meteorological data with a Geographic Information System (GIS).

A Mighty Long Rope

Tracking a cold front with satellite imagery is easiest when there's a rope cloud. Formed by the sudden uplift of moist air to the Lifting Condensation Level (LCL) by the hydraulic head of a surface density current, rope clouds are linear features that rarely produce significant precipitation. In some cases they may also be associated with thunderstorm outflow boundaries or mesoscale fronts. Usually their position will correspond very well with the location of the surface discontinuity, although this can vary some in cases like "tipped over" fronts where cool water surface temperatures inhibit the surface front. In some cases kinks or intersections of multiple rope clouds can help to localize uplift sufficiently to initiate thunderstorms. Generally the low cloud top height and narrow scale of rope clouds make them much easier to see with visible imagery than with infrared. An example over Florida was studied by Seitter and Muench in 1985.

Today there is an unusually long rope cloud feature, spreading in a pretty much continuous line from Ontario to Texas. The position of the cold front can be identified also in New Mexico, by the presence of upslope stratus. Comparison with the RUC analysis of equivalent potential temperature confirms the strong density discontinuity. The decreased gradient across the front in West Texas is related to the presence of a short dryline feature in northeast Mexico. A weak outflow boundary from the prefrontal convection extends across from San Antonio to southern Mississippi.

The Yellow-Green Rain: Pollen

Well, it's really springtime in Mississippi now. I almost want to have an umbrella when I'm in the yard to keep the pollen from falling down on me. Of course, that wouldn't keep it out of my nose. Luckily it's not bothering me nearly so bad as it's bothering my children. After running around outside, they come inside looking for Kleenex to wipe their sniffly noses. Over the weekend their allergies were bad enough at night to significantly cut into my sleep.

One factor in the pollen problem is the fact that we haven't had significant rain in several days. Air quality and pollen levels normally improve after rain, due to the "scavenging" effect of the raindrops in removing aerosols from the atmosphere. Of course, the moist conditions can also help to trigger the release of more pollen. A big obstacle to better coordination in research, understanding, and forecasting of health impacts from weather is that we have very little idea what is floating around out there on any given day, especially for global transport. It is fairly well established that a significant proportion of aerosols are biogenic, such as pollen. But it is still quite difficult to routinely collect and identify them.

And we really don't know how large of an impact biogenic aerosols may have on the weather and climate. Potential direct impacts could include nucleation of cloud droplets and radiative interactions. Some of the issues involved were discussed in a 2005 article in the Bulletin of the American Meteorological Society. The role of aerosols is also summarized in this NASA brochure. Or you can check out the slightly sensationalized article "Airborne Dandruff Can Turn On Rain" from Australia.

Satellite Imagery Today

There was a good example of marine fog confined by topography today along the Pacific Coast from San Diego into Baja California:


And here's some lake ice up in the Great Lakes area:

Finally, there was a good example of upslope stratus in southern New Mexico. A shallow cold front pushed relatively cool, moist air up the eastern slopes of the Capitan Mts., Sacramento Mts., and Guadalupe Ridge:

Science Fair season

Today and tomorrow the Mississippi Region II Intel Science Fair is being judged here at JSU. Over 1500 students are participating this year. Several entries this year relate to atmospheric sciences. Judges were reminded this morning by Dr. Mark Hardy (Dean of the College of Science, Engineering, and Technology) of the declining interest among American students in scientific careers and the potential role of science fairs for building students' enthusiasm for science. Also, the regional fair gives a rare opportunity for so many pre-college students to get a glimpse of the university.

Springtime Up North and Lake Fluctuations

Looks like folks up in Minnesota will be getting some more spring snow.

On the other hand, the closed basin of Devils Lake in North Dakota is dealing with a long-term rise in lake levels. Such endorheic (closed-basin) lakes are particularly hard to deal with during climate fluctuations since there is no outlet for water during unusually wet years. Other notable examples in the United States are the Great Salt Lake in Utah, which reached its highest observed level in 1987; and the Salton Sea in California, which was much larger hundred of years ago but basically dry during the 1800s. Even in the case of the naturally exorheic Great Lakes, water levels can fluctuate by several feet.

Spring Flooding

Major flooding in Arkansas over the past few days will contribute to moderate flooding on much of the lower Mississippi River.

Recent weather of interest

The biggest weather story over the weekend was probably the tornado that ripped through downtown Atlanta. In other news though, there have been significant weather problems in the Southwest, including whiteout conditions in Northern Arizona.

A bit farther away, the folks in Britain are also getting hit hard by a major winter storm system. Then there's the tornado that was reported in the Philippines. And down in southern Africa, they're dealing with the aftermath of Tropical Cylone Jokwe, which hit northern Mozambique over a week ago. If that's not far enough away for you, then consider the massive storm recently observed near the south pole of Venus.

Spring Break!

Well, Spring Break 2008 has now begun, for JSU and for most other students as well. Although the stereotype is that all college students go to party at an exotic beach during the Break, economics and family ties result in a lot of folks just relaxing at home for a week. Wherever you are though, it must be considered that the weather can be pretty fickle in March. Those of us that are starting to (reluctantly?) get older can think back to the Spring Break chaos of the "Storm of the Century" in 1993. In that case, different parts of the country were hit with tornadoes, storm surge, and blizzard conditions all from the same system. In all, about 270 people were killed and as much as $10 billion in property damage was sustained. It was also one of the greatest successes of modern numerical weather prediction.

Although it's probably too late to get in on it now, some "weather geeks" might like to spend their Spring Break storm chasing out on the Great Plains. Fun stuff, possibly. Or boring, if nothing happens. In any case, the excitement of a powerful storm is never an excuse for ignoring the suffering of storm victims. Most recently, let's not forget the devastation from the F4 tornado that hit Jackson, TN on Feb. 5.

Of course, even if you are on the beach in Cancun and the weather turns out gorgeous, you still need to be careful. Besides opportunities to indulge in immorality that can put your life on a fast track to disaster, you shouldn't forget that too much solar radiation can be a very bad thing. In particular, it's the ultraviolet (UV) radiation that gives sunburns, contributes to skin cancers, and can harm your eyes. Just think how bad it could be if we didn't have ozone in the stratosphere to absorb over 98% of the ultraviolet radiation before it can reach the earth's surface! Protect yourself with lots of high SPF sunscreen, and not leaving a lot of exposed skin when the sun is highest in the sky.

And don't forget to come back to class after the Break.

Weather Camp 2008

After skipping last year since I was out of state, we are now making plans to host JSU's summer Weather Camp again. The dates have been set for June 2-6, and applications are requested from interested high school age students. This educational day camp is sponsored by the NOAA Center for Atmospheric Studies, of which Jackson State is a part. The selected students will receive a modest stipend upon completion.

So what do we do during a Weather Camp? Besides interactive learning about weather and the atmosphere, there are field trips to weather observing sites, the National Weather Service office, a television studio, etc. Participants also prepare a short presentation on a topic of interest to them.

Do you know of a youth who has an interest in weather and climate? Encourage them to apply today! We plan to accept applications through the end of April. Information and application guidelines will be posted on the website. Any questions?

A Snowy Winter

On March 9, Central Mississippi saw snow for the second time this year. Unlike the January event, this time the snowfall was concentrated in Northwest Mississippi, mostly in the Delta. The best summary of this late snow event is on the website of the Jackson NWS Weather Forecast Office (WFO).

So what does it take to get snow in Mississippi? Most of the significant events tend to be associated with Gulf lows that intensify in the western Gulf of Mexico, tracking up towards the Mobile area. If a cold enough deep layer of air is over the Southern Plains and everything works out just right, it can interact with the Gulf of Mexico moisture to produce some frozen precipitation. The positioning of the Gulf low is crucial in order to provide advection of cold air from the northwest, as well as some overrunning or wrap-around Gulf moisture. Making sure that the winter storm is a snow storm, instead of freezing rain or sleet, depends a lot on the thermodynamic/temperature profile in the lower troposphere and the cloud physics.

It's been a snowy winter up north as well. The same storm that brought snow to Mississippi also brokes some records up in Ohio. Seasonal accumulations have been especially extreme in much of Eastern Canada. In Quebec, they're even starting to get violent about it. Look at how deep the snow has gotten in New Brunswick!

Welcome to DoWaC!

The weather's fine, spring is in the air, and mid-terms are past again. It's a great time to start a new blog. While I'm hoping this will especially be a useful forum for my Meteorology students here at Jackson State University, I intend to use it for discussion of a wide variety of topics relating to weather and climate. Suggestions are of course welcome. We may try to do different themes according to the day of the week, depending how the flow goes.

Some posts will be specifically designed to relate to current class topics. Others will deal with current weather events, online resources (including other blogs), research topics, professional development, weather/climate impacts, etc. Of course, I'll be a lot more motivated to develop the blog if I get good participation via comments.

If you are not a JSU Meteorology major, then come on in anyway! The broader the base of discussion, the better the blog will be. I would of course ask that the discussion be kept civil, positive, and reasonably close to the topic. It would also be nice if everyone could double-check their comments for correct spelling and grammar before publishing. When posting for the first time, please try to give clarification whether you are a JSU student, atmospheric science professional, general public, or whatever.

Now, about the JSU Meteorology Program. We are a small (3 faculty) program granting Bachelor of Science degrees in Meteorology. Currently JSU is the only historically black college/university (HBCU) offering a B.S. in Meteorology. So yes, we do think we're kinda special. And we like to think that each of our students is special.