Snowstorm in England

Southern England (in particular London) is recovering from a rare heavy snow yesterday that largely shut down transportation. Because of the rarity of significant winter weather, preparations were of course not what would have been done in a colder place. The approximately 10 inches accumulation is the greatest since 1991.

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.