Big Heat Week into July 4th Weekend

[pazzo83]

big surprise that the 80+F lows are official in DC, Philly, and NYC.  Heat index of 99F at DCA at 1am - lovely.

[yoda]

1 minute ago, pazzo83 said:

big surprise that the 80+F lows are official in DC, Philly, and NYC.  Heat index of 99F at DCA at 1am - lovely.

87/77 at 1am... yuck

[adelphi_sky]

Just got back from Ocean City. It was a nice 84 degrees. On the boardwalk, there was a nice breeze. Sometimes warm, sometimes it felt like 70 degrees. Had to wrap up on the beach at 5:30pm at 81 degrees and a stiff chilly breeze. 

Got back home and 86 at 1am. Wow. 

[yoda]

3 hours ago, yoda said:

87/77 at 1am... yuck

86/72 at 4am.  HI 92

[yoda]

From this morning LWX AFD 

Record temperatures will continue through much of the upcoming
Independence Day holiday weekend. An upper ridge remains parked
across a vast portion of the southeastern U.S. into the
Tennessee/Ohio Valleys and Mid-Atlantic region. Lower
tropospheric temperatures remain very anomalous and record
breaking in nature. Of note, the 00Z IAD sounding reported an
850-mb temperature of 25.0 C which is not only the 3rd highest
of all time, but breaks the daily record by over 4.0 C.

Recent 00Z models show a subtle decrease in these 850-mb
temperatures. However, based on yesterday`s observations, models
have been slightly too cool with this layer of the atmosphere.
Thus, see little reason to diverge from another hot forecast
with widespread temperatures punching into the 98 to 102 degree
range. Even during the writing of this discussion (~3 AM), a
number of the warmer spots remain entrenched in the upper 70s to
mid 80s. High dew points should also remain a fixture in the
forecast with readings holding steady in the low/mid 70s.
Although some boundary layer mixing could slightly lower such
dew points, the combination of triple digit highs and low 70s
dew points will easily crank heat indices to around 110F.
Extreme Heat Warnings continue from 10 AM until 9 PM across a
bulk of the Mid-Atlantic region. For those in the Blue Ridge,
Alleghenies, and across the central Shenandoah Valley, heat
indices around 100 to 104 degrees supports Heat Advisories
today.

 

[yoda]

So far, and probably still have about 2 more hours to go... but the low temp at DCA is 84

[CAPE]

Low of 76

Forecast high is 103. Made it to 99 yesterday with a forecast high of 102.

[hstorm]

Looks like pur low here will be 77. Yesterday was 99/76. 
 

today feels like it will be hotter. Swim meet this morning should be fun …

[Eskimo Joe]

Several mesonet sites, even rural ones, are in the low 80s.

[dailylurker]

82 imby. Made it to 101 yesterday. Dreaming of chasing extreme lake effect snow. I can vision that black clouds against that arctic blue sky as the energy builds over Lake Ontario. Watching the radar light up with yellow and orange as the band gathers strength and moves right at your location. It's super exciting. It's like chasing severe thunderstorms but more fun imo.

[Paleocene]

Went for a jog just now before the sun goes above the treeline in my nhood. Great way to start sweating in sixty seconds! We're bailing and headed out to WV later this am... Maybe it will be 95 instead of 101 lol

[MN Transplant]

3rd highest 850mb sounding temp on record is extremely impressive.

[kgottwald]

8 hours ago, vortex95 said:

And it claimed that "much higher humidity" for the heatwave today (compared to the 1936 heat).  Is that really true? 

Local Climatological Data reports from back then didn't even include dewpoints, nor are they available on XMACIS. Getting that data is really difficult.

[TSSN+]

Looks like DCA only got down to 83 or 84 

[kgottwald]

Even at the mouth of the Amazon, nights never get this hot!!

https://en.wikipedia.org/wiki/Belém#Geography

note that temp averages year-round are just "normal DC July".

[Mrs.J]

Looking at my station data we got all the down to 77 this morning at 5:54 am. Cranking back up though. Currently at 82/76/90.

[nj2va]

82 for the low at home in Alexandria. 70 for the low at Deep Creek. 

[astarck]

DCA’s heat index never dropped below 90 last night. 

[MN Transplant]

We'll see in 15 minutes or so whether some all-time records have been tied.

 

==================================================================
                  *** ALL-TIME RECORD WARM LOWS ***
==================================================================
Baltimore                  83 (set on Aug 05, 1930 + 2 other times)
Washington                 84 (set on Jul 24, 2011 + 2 other times)
Sterling-Dulles Airport    79 (set on Aug 08, 2007)
Baltimore Downtown         88 (set on Jul 22, 2011 and Jul 10, 1993)
Annapolis                  92 (set on Jul 07, 1994)
Hagerstown                 86 (set on Jun 15, 1899)
Martinsburg                86 (set on Jul 21, 1930)
Charlottesville            85 (set on Aug 07, 1918)