George BM

Dulles at 96/73.

Fifth 95+F day in a row at IAD.

IAD bottomed out at just 79F this morning! Thankfully dewpoints were a bit lower with a slight breeze or running outside would have been torture. It was still quite a bit warmer than ideal for sure though. Back to the 79F low at IAD. If we don't get below that by 1am tomorrow morning (that would be midnight going by standard time which the NWS uses) It will tie the all-time warmest daily low there.

IAD at 98F. 98/70

Decent gradient indeed. 2 tenths of an inch IMBY.

Long-range CPC guidance HAS been showing June 25, 2006 as a top analog for a few days... not that it means it will be anything like that of course. Just showing the general pattern long-range guidance sees.

Forecast Discussion Thursday, July 25, 2024 2:34PM EDT Excessive Heat Warning in effect until 8PM EDT Thursday, July 25, 2024 PDS Severe Thunderstorm Watch in effect until 10PM EDT Thursday, July 25, 2024 Much of the region will finally see a decent amount of rain this afternoon and evening. The major caveat, however, is that it will come in the form of significantly severe thunderstorms with the threat of life-threatening hurricane-force wind gusts, large hail and a few tornadoes. A record hot and moist airmass remains in place ahead of the SSE advancing cold front with temps generally between 102 and 105F combined with upper 70s dewpoints leading to heat indices as high as the 120sF. The cold front bringing the relief from this extreme heat/humidity will, unfortunately, lead to dangerous storms as the afternoon progresses. Temperatures may rise another degree or two into the mid 100s. (103-106+F) with heat indices of 118-125+F. Storms have already begun forming along and near the cold front to the northwest from southern PA west/southwestwards into far northwestern MD. With the extreme environment in place ( 9+C/km low-level lapse rates, up to 2000 J/kg downdraft CAPE, 2.25”+ Pwats, 3500-5000+ J/kg MLCAPE all combined with 40-50+ kts of effective-bulk shear) storms will quickly congeal into ESE-moving bowing segments which may produce corridors of destructive, hurricane-force wind gusts, in some cases potentially up to 100+mph with the embedded micro/macrobursts the environment will be very favorable for. With large CAPE through the hail growth zone, storms could produce large hail as well with 2”+ diameter hail possible with any embedded or lone supercell. Low-level effective SRH will be moderate (~100-150+m2/s2) which will be enough for a chance of a few qlcs tornadoes across the region, particularly with the bowing line-segments. With the high moisture content of the atmosphere, these storms will also be efficient rain producers with 2 to 3+ in/hr rainfall rates leading to ponding and some instances of flash flooding despite the dry conditions over the last several weeks, though the flash flooding threat doesn’t look widespread enough to warrant a Flash Flood Watch at this time. Trends will be watched over the next few hours for possible future issuance. Most areas will most likely receive between one and two inches of rain with some spots the end up under brief training, particularly between the bowing segments, may end up with up to 3 inches. Wherever this occurs will experience the greatest flash flooding risk. Once the front moves through the region by the mid to late evening hours skies will clear and temps will fall into the upper 50s by dawn on NNW winds of 15 to 20mph, gusting over 25 mph at times. Friday will feature the coolest day since early/mid June with temperatures only reaching the mid/upper 70s with low humidity. Weenie Forecaster Wannabe: George BM

Glorious first day of July on tap with below normal temps and low humidity.

IAD with a late high of 97F currently.

Meanwhile... still at 86/71 at IAD at this late hour.

What stands out for me in my personal experience this month is the lack of audible thunder. I may have heard a distant rumble with the tornadic supercells (June 5th) and another distant rumble on June 14th. But other than that... nothing. I was surprised to not hear any thunder with the activity June 26th.

As of Tuesday morning: Widespread moderate drought

DCA +3.3 NYC +2.2 BOS +1.7 ORD +2.2 ATL +3.0 IAH +1.9 DEN +0.7 PHX +1.2 SEA -0.7 (temp anom in F)

If nothing else, these dry conditions that we have should help further steepen LLLRs w/ solar heating (quicker heating of a dry surface... a + for wind potential).

Unsurprisingly, I've been seeing an increasing number of sprinklers active in my neighborhood on my morning runs. 87/50 at IAD following a nice 57F low.

For June 23, 2024 IAD had a record high of 98F yesterday. But more impressively only bottomed out at 78F for the warmest June low on record. This breaks the previous record warm June min of 75F set... the previous day (June 22, 2024).

I think the 36 refers to their relative humidity. 36%

IAD with a 10pm obs of 90F. Lol

lol BWI has 101F for the 4pm hourly ob.

This is the earliest 100F reading in a calendar year at Dulles. The previous earliest was on June 27th of 1964.

A one-minute obs of 100F at IAD! ETA: Now two minutes. IAD has hit 100F.

IAD now at 99F. Very close.

IAD has hit 98F so far. Hot.

Unsurprisingly, a heat advisory is now up for tomorrow as well. IAD has hit 96F so far.

Also, the record warm daily minimum temp for June at IAD is 74F. It got down to 75F this morning and with storms/convection looking very unlikely...