Thursday, April 13, 2006

DC: Deficit Capital

A very weak frontal boundary moving through early this afternoon touched off some thunderstorms in the southern portion of the Washington DC region. Moving southeastward from Fauquier and Prince William Counties in Virginia, the storms crossed the Potomac into Charles County, where they prompted a severe thunderstorm warning, which was cancelled shortly after 3pm. Site visitor PC reported nickel-sized hail in eastern Prince William.

At post time, radar showed some scattered light activity south of the District, but the earlier area had intensified over the lower Chesapeake Bay, just south of the mouth of the Potomac. For the rest of the afternoon and evening, a few more isolated storms could pop up, but conditions will be mainly dry. See Josh's post below for the chances of receiving some much-needed rain over the weekend.

Surface weather map and satellite picture at 2pm today from HPC/NCEP/NWS

Tonight and Tomorrow

Lows tonight will remain quite mild for the season, mid to upper 50s, under partly cloudy skies. Today's models are showing an unusually wide range of temperatures for tomorrow, but a consensus target somewhere in the mid 70s looks reasonable, with sun through broken to overcast skies. The chance of showers, especially in the afternoon, is 40%.

Deficits Matter

The Nation's Capital has been the home of "Red Ink Run Amok" for quite some time, but it is also recently experiencing a deepening precipitation deficit. The chart shows the accumulated precipitation this year as a percentage surplus or deficit relative to the long-term average. Following a January which was almost exactly "normal", early February was quite wet, but the surplus was more than wiped out by the record-breaking dry March, and the rain so far in April has barely maintained the status-quo. Although a holiday weekend is coming up, that sound you hear is from the lawns and shrubs throughout the region crying out for more moisture. chart from NWS data, photo © Kevin Ambrose

No comments:

Seasonal Outlook

Latest seasonal forecast: Click here.

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