George BM

Beat me by 0.08".

Welcome to Meteorological Fall! It will feel like it eventually. I promise.

Monday, September 7, 2026 8:25AM EDT The past week has been one of the most active weeks of stormy weather in the region for a very long time with multiple MCSs and derechos causing repeated instances of widespread tree damage and even some structural damage with the northwest flow around the ridge of high pressure that has been parked to our west-southwest. During the September 1st through September 6th period much of the region has received 8 to 14 inches of rain with most areas seeing peak wind gusts from severe thunderstorms during this period in the 70 to 85 mph range. Now we watch as a deepening trough drops into the region with causing the flow locally to back to southerly. With a surface low developing nearby over the region in response to this trough southeasterly surface flow will bring in mid 70sF dewpoints into the region. With Pwats also rising above 2.25 inches and CAPE in excess of 1,000 J/kg along with tall skinnier CAPE profiles. Storms that develop will be very efficient rain producers. With the strongest forcing for accent located over the region numerous storms will be able to develop and train over the same areas leading to a significant flash flooding threat given all of the recent rain. Numerous bands of showers and thunderstorms will train over the region from late morning through this evening before we see a more uniform area of heavy rain over the region through the night tonight as the surface low strengthens and moves to the east over the northern Chesapeake. There will be a risk for a few tornadoes through the afternoon with embedded supercells given decent low-level shear near the surface low (effective SRH of up to 300 m2/s2) and decent enough 0-3km CAPE (>100 J/kg). When all is set and done by tomorrow morning most areas would have received an additional 3 to 6 inches of rain with localized areas that get under training bands in excess of 10 inches leading to major flooding. Always remember to turn around don’t drown. It’s not worth it! ...

Advisories on Tropical Storm Dolly being initiated at 11 o'clock ante meridiem.

Great write up, @WxWatcher007!... No. I haven't read the whole thing yet. I just know it's great.

https://schumacher.atmos.colostate.edu/hilla/csu_mlp/csu_severe.php

Correct.

Severe Thunderstorm Watch out until 9pm.

This! Getting a moderate shower with barely any evidence of it on radar. That's how you know the low-levels are juiced.

Last month of meteorological summer! Home stretch!

Tuesday, August 4, 2026 11:38AM EDT Skies continue to clear from west to east following this morning’s rain and storms. Much of the region generally picked up between half an inch and an inch of rain. As we go through the afternoon temps will rise into the lower 90s w/ dewpoints getting into the mid/upper 70s leading to 3000-4000 J/kg MLCAPE beneath the 6.5-7 C/km MLLRs. As the unseasonably strong shortwave approaches from the west it will most likely bring with it a complex of thunderstorms congealing into a severe MCS. At the same time, a couple of supercells may develop over the region ahead of the main cluster and with near 60kts of EDWD and effective SRH in excess of 250m2/s2 these have the potential of producing strong to intense tornadoes. SPC has us under a 10% CIG1 tornado risk to account for this. We are also under a 60% CIG1 wind risk resulting in a level 4 out of 5 Moderate risk of severe weather. With the high CAPE, decent DCAPE (1000+ J/kg) and high Pwats around 2 inches, the MCS could bring widespread 65 to 80+ mph wind gusts across the region with even higher gusts in any embedded microbursts resulting in widespread and potentially long-lasting power outages along with major tree damage and some structural damage to boot. Stay tuned to the evolving weather situation and take all the necessary precautions.

Just a lightning barrage with that eastern Loudoun county storm.

June 5, 2024 in northern MD.

90/77 at IAD.

Yeah only down to 81F on the day so far. If no rogue storm pops up later we could at least tie the all-time or have the first 80+ daily low there. (You, of course, know this. I just like talking sometimes. ) ETA: LOL! I should've read the post above before commenting. I was still on the last page.

Yeah that's a code 'Maroon' for sure.

IAD at 99/73.

Picturized.

Wonder if we get an 18z sounding from LWX today.

Temperatures were in the low/mid 80s for my pre-dawn run this morning. Way too warm. Was probably lot too far away from heat exhaustion at one point. Hydrate! IAD currently at 92/72.

IAD at 93/77 currently.

88/75 at IAD before 9am.

IAD has hit 98F so far.

IAD 93/76 at 11am.

Currently 87/75 at IAD 8:44am EDT.