Thursday, April 5, 2007

Back to the Future

** Freeze Warning in effect 11 PM tonight to 10 AM Friday **
** Freeze Watch in effect late Friday night through Saturday morning **


Cold, windy. Arctic air arriving on blustery northwest winds pushed temperatures back to wintry levels today in the Washington metro area. It took until 3pm for the official reading to get back to its midnight level of 46°. Some scattered flurries were reported in the area, but radar at mid afternoon showed flurries mainly limited to north of the Mason-Dixon line and west of I-81.

As a strong upper-level low pressure vortex continues to rotate counter-clockwise in southeastern Canada, temperatures will remain cold through the weekend, and there is the likelihood of some snow showers or flurries. At least one model is attempting to develop a storm off the Delmarva coast by Saturday morning, but that is not confirmed by the early model run this afternoon.

Tonight and Tomorrow

Cold. Under mostly clear skies, lows tonight will be near freezing downtown to the mid 20s in 'burbalonia. Tomorrow will be very similar to today, with variable clouds, a little less wind, and highs in the upper 40s.

For the outlook through the weekend, scroll down to Dan's post below.

Climate Corner

Also returning to the spotlight this week is the Intergovernmental Panel on Climate Change (IPCC), whose Working Group II report, "Impacts, Adaptation and Vulnerability" will be released tomorrow at a press conference in Brussels. The WaPo obtained a nearly-final draft; a front-page article today, "Climate Panel Confident Warming Is Underway", discusses the report's expected conclusions. The online WaPo also posted an article, "Report: Global Warming to Change Climate of American Southwest", this afternoon reviewing the implications of climate change in the Southwest U.S. The main conclusion is that rainfall is expected to decrease 10-20% by the end of the century.

The Weather Channel is planning to provide daylong coverage tomorrow of the new IPCC report. Check your favorite squawk radio and cable noise networks for the predictable Gore-bashing.

Wednesday, April 4, 2007

Spring is Busted Out All Over

** Freeze Watch in effect from late Thursday night through Saturday morning **


Cloudy, chilly. Persistent clouds and an easterly wind following this morning's showers and thunderstorms have busted numerous forecasts of warmer readings in the Washington metro area this afternoon. At mid afternoon, temperatures were generally in the low to mid 50s, while even colder air is poised to arrive for the rest of the week and weekend along with the possibility of some snow showers.

All three major local airports reported thunderstorms early this morning, but these had all moved well offshore by early afternoon. Some sun was peeking through the clouds late in the afternoon.

Photo of cherry blossoms earlier this week by photographer Kevin Ambrose

Tonight and Tomorrow

Decreasing clouds, colder. Clouds will decrease and winds will increase overnight as lows drop to the mid and upper 30s in the city and near freezing in the coolest parts of 'burbalonia. Tomorrow will be partly cloudy and breezy with highs in the upper 40s to near 50°.

For the outlook through the weekend and beyond with Larson's Long-Range, scroll down to Josh's post below.

Tropical Topics: Meet the Hurricane Guy

This month's meeting of the local chapter of the American Meteorological Society features the new Director of the National Hurricane Center, Bill Proenza. His presentation topic is, "Challenges in Warning and Prediction of Tropical Cyclones". The meeting at the new Rockville library begins with a light dinner at 6:00 next Wednesday, April 11. Cost is $15 for members and $20 for non-members. RSVP information (deadline Monday) is on the meeting web page.

Seal Hunt Impacted by Ice Conditions

Today's WaPo, in a story headlined, "Warming Thins Herd for Canada's Seal Hunt", reports that the beginning of the annual Canadian seal hunt has been affected by poor ice conditions in the Gulf of St. Lawrence: "Canadian authorities reduced the quotas on the harp seal hunt by about 20 percent after overflights showed large numbers of seal pups were lost to thin and melting ice in the lower part of the gulf, off Prince Edward Island." Among other press reporting on the event are the Winnipeg Sun and The Economist.

Tuesday, April 3, 2007

As Good As It Gets


Beautiful! Clear skies, warm temperatures, low humidity, and a light breeze have combined for a nearly perfect spring day in the Washington metro area. Unfortunately, that's as good as it's going to get for now as wintry temperatures stage a comeback by the weekend. Temperatures by mid afternoon were generally in the 80s, although an easterly breeze kept National and Quantico in the mid 70s.

Tonight and Tomorrow

Increasing clouds, showers developing. Clouds will increase tongiht with lows in the low to mid 50s. There is a 50% chance of showers overnight. Showers are likely tomorrow morning, but clouds will decrease during the afternoon with highs in the mid 60s, falling late in the day.

For the outlook through the rest of the week and weekend, scroll down to Jason's post below.

Tropical Topics

The updated Klotzbach-Gray statistical hurricane season forecast was released today at Colorado State. The outlook is similar to the earlier one from AccuWeather, but without the Bastardi Bombast. As the result of a rapidly weakening El Niño, it calls for a more intense season than the forecast originally made in December. The current expectation is for the following (long-term averages in parentheses): 17 (9.6) named storms, 9 (5.9) hurricanes, 5 (2.3) intense hurricanes. The probability of a landfall by at least one major hurricane is: 74% for the entire U.S. coast, 50% for the East Coast (including Florida peninsula), and 49% for the Gulf Coast.

Political Science

Yesterday's Supreme Court ruling against the EPA's position on greenhouse gas regulation was widely covered in the press, both the dead-tree and silicon-based versions. In the WaPo, it rated both a Page A1 lead position and an editorial. The WaPo's Bench Conference legal blog has a rundown of links to the usual suspects. Whether this court action leads to any real world action, of course, remains to be seen.

Seasonal Outlook

Latest seasonal forecast: Click here.

Latest 3-month temperature outlook from Climate Prediction Center/NWS/NOAA.