11:00 p.m. update: Area of storms has expanded while the most severe storms have weakened. No warnings are in effect. Storms stretch from Baltimore through Columbia into western Frederick county. Some storms are developing outside of this main line in Loudoun county and northern Prince George’s county as well as northern Anne Arundel county. The whole complex will move east and southeast carrying some heavy downpours and lightning and probably weaken some. Most likely places to be affected stretch from the north side of the beltway and to the east and northeast. Outside of that, storms will be isolated. Everything should wind down by 2 a.m. or so.
10:10 p.m. update: Some strong to severe thunderstorms with a history of producing hail to 1” in diameter are moving through sections of Frederick, Carroll, Howard, and north and west Montgomery county. Severe thunderstorm warnings are in effect through 10:45 p.m. After this time the storms should roll through Baltimore. Follow radar and the Twitter feed below for the latest updates (requires reloading page for latest tweets).
The surprising cool, marine layer capped temperatures this morning, but a surging warm front coupled with May sunshine pushed afternoon temperatures to 80 and higher. A couple isolated storms could drift into western parts of the region this evening. Otherwise, it’s mild overnight and summery on Friday, with somewhat better late day storm chances.
Through Tonight: West and northwest of the beltway, there’s a 20-30% chance of showers and thunderstorms before 10 p.m. Elsewhere, odds are less than 20 percent. Skies are partly to mostly cloudy, with lows 60-65 (suburbs-city).
Friday: Partly sunny and very warm and humid - more like June or July than early May. Highs reach 82-88 (northeast-southwest) with light winds from the southwest. Towards the late afternoon and evening, there’s a 20-40% chance of thunderstorms - highest odds again to the northwest. A few storms may be strong to severe with damaging wind and hail potential.
Pollen: Trees are MODERATE at 71 grains/cubic meter (compared to 211 Wednesday). Grasses are HIGH at 7 grains/cubic meter. Mold spores are LOW.
Hasta La Vista La Nina: From the excellent blog Wasatch Weather Wennies - Today the Climate Prediction Center issued it’s “final La Niña advisory,” which marks the end of this latest La Niña episode. As discussed in the advisory, La Niña is unlikely to redevelop this year. The long-range outlook is for neutral (meaning no La Niña or El Niño conditions) or El Niño conditions later in the year.