vortex95

Laptop shock again? Or power pole fire?

K16J - Dawson GA K9K7 - Ellsworth KS KI93 - Hardinsburg KY KLKP - Lake Placid NY KMKV - Marksville LA KPBM - South Timbalier 232 LA 28.617 -90.338 35m KS31 - Lopez WA KX59 - Valkaria FL

Providing historical context is not pushing an agenda. No wx event should be treated in a vacuum, but that is what done a lot these days, hence everything is "worst ever" or "unprecedented."

The worst heat wave on record for the East occurred before this date range in 1911. https://en.wikipedia.org/wiki/1911_Eastern_North_America_heat_wave BOS hit 104 on July 4th. So is 11 days earlier in 2025 low 100s in BOS really that extraordinary or that early, relatively speaking, esp. since avg temps everywhere are up by "alarming standards" in the last 100+ years? And add in the UHI effect at many climo sites, and things aren't quite as impressive as they appear. I would argue this levels things close to equal as to as far as extremes go for the region. Facts are meaningless w/o context.

Usually in FL, the 80 DPs are confined to immediate coastal areas. I do not think BOS has ever had a 80 DP. 78 or 79 max.

I don't see any indication DPs hit 80 in eastern MA or anywhere in New England from the standard airport observations. Highest I could find is 78. And DPs were lower near the coast from the sea breeze.

Go to OWD airport for the max effect!

Something to keep in mind for the larger pix (video link attached). ASOS was not really designed for climate data, it's more for aviation. And for aviation, temp is a secondary priority, compared to ceiling, vis, wind, and altimeter. And don't get me started about AWOS, esp. for dew points (they run high often and worse as you get in the 60s and higher). Seen this many times for OK. Compare the mesonet w/ all the ASOS/AWOS temp/dews, and it is apparent.

"I want 100! -- fail otherwise!" LOL.

One thing to keep in mind is that MWN's all-time record high us 72 set on 8/2/1975 and 6/26/2003. If the GFS is showing "only" 66, that is of concern for lower elevation max temps fcst. 8/2/1975 was ideal dry NW flow subsidence for highest temps on record in much in New England, and we do not have this pattern currently. And on 6/26/2003, general 100-103 did not occur in New England. CoastalWx needs to do something about OWD temps! Closest ASOS to him, so he has a vested interest! And talk about bad sensor or their placement, look at Baltimore/Inner Harbor today. Site is poorly located (not at an airport) and obviously contaminated by the concrete jungle or something like AC units nearby. General city UHI is not *that* strong during the day. : First-order and climate sites BWI : Balt-Wash Marshall : 97 / 76 / 0.00 CHO : Charlottesville AP : 96 / 72 / 0.00 DCA : Reagan National AP : 98 / 76 / 0.00 DMH : Baltimore Inner Hrb.: 104 / 85 / 0.00 HGR : Hagerstown Rgnl AP : 98 / 76 / 0.00 IAD : Dulles Intl Airport : 96 / 71 / 0.00 MRB : Eastern WV Rgnl AP : 97 / 81 / 0.00 NAK : Annapolis Naval Acad: 94 / 77 / 0.00

Look at these GIF loops from late this aftn. Classic supercell split mirror pair in n-cntrl MD. The left split accelerates and moves N, and the right split moves ESE and is slow-moving. In a more unidirectional environmental flow w/ wind shear, the supercell splits both have an equal chance of surviving. Most of the time tho when there is directional shear present, it is veering w/ height, so that favors the right mover (cyclonic meso), and the left mover (anticyclonic meso) does not last long. Supercells by default split, but often since the right split is so favored so often from the shear profile, the left split never has a chance and is wiped immediately, so you see nothing on radar! And when overall flow is weak/disorganized over an area, the mesoscale takes over, leading to some odd storm motions and evolutions, as we see today.

FWIW, this is what it looked like just to the N of College Park at 5pm today. It tried for a brief time. Definite supercell with a long inflow band to the E. I had to take this pix through a window.

There are these wx sayings, "similar patterns breed similar storms" and "when it's good, it can be REAL good!" First, I will get this out of the way, CoastalWx is once again STEAMED this did not happen in this past winter! This storm is almost a carbon copy of the last storm, except everything is ~100 mi NW. The 500 trough evolution is ideal. The trough over the Mid-Atlantic is at first neutrally titled, and does a full 90 deg swing negative as it moves across New England. That's how you do it for a classic! The last storm did this as well. 982 mb for a central pressure over New England is very impressive for late May. I can not recall a low this deep here this late, esp. over land. Embedded tstms look to be widespread, even the cool sector of the storm. Few hundred CAPE is common across the region on the models as the storm winds up. That does not happen often w/ a Nor'easter, but given it is late May, by default you will have some CAPE around. Big R+ potential in western sections w/ the deformation. Can it look any more classic on the HRRR forecast radar valid 18z Sat? Snow once again likely in the mtns (above 4000 ft this time) and probably several inches on Mt Washington as a rather cold air mass for this time of year flushes in behind the storm.

Feedback period open through 6/26 https://www.weather.gov/media/notification/pdf_2025/pns25-37_mag_webpage.pdf Site in question. https://mag.ncep.noaa.gov/model-guidance-model-area.php

Oct 22-23, 2014 CG plot and IR attached. Blue Hill 6.18" for the storm. One thing I recall about this event is the gusty/bursty winds well before the precip stared, even inland. Why? B/c there was CAPE/lifted index negative in the region as the storm approached and the gradient increased. Much more efficient mixing down of the BL winds in such an environment, which is rarely seen pre-nor'easter in New England!

Precip plot for this past storm clearly shows the mesoscale "thingee" track over sern MA. Mesolows are notorious for enhancing rainfall. Broad rotation increases updraft strength and low-level convergence locally. The mesolow also explains the unusually high LTG density for a Nor'easter, and also the fact given it is late May, climo says there is just more convective instability around in the mean. What was amazing is the apparently the HRRR caught on to this feature 24 hr before, showing an enhanced swath of R++ S Coast of MA to BOS. Last time there was this much LTG in a Nor'easter here I think was Oct 2014. Need to check my archives on that when I get home. CoastalWx may be able to pinpoint this one!

I moved to Silver Spring MD in 2020 for a job after living most of my life in Woburn MA. The avg temp yearly in DCA is 6 F higher than BOS, and the DPs are relentless in the summer, esp along Chesapeake Bay where they get to 80 F often. My first two summers here, I was sweating a lot, but by the third summer, it was not nearly as bad. Point I am making is that the body adapts to warmer (or colder) temps in a relatively short period time w/ no ill effects. But that nothing to to what happens in the Middle East along the Persian Gulf, specifically Qehsm Island, Iran. Dew points every summer get into the 90s, and typically in August it really maxes out. Two years ago, it was 100/97 around sunrise one day and last year the same. The METAR (OIKQ) reports I have checked over time, and the temp/dp are valid based on the wind direction, SSTs, and other factors, such as FG present or not. Population of the island is 150k, and many do not have AC. Yet they do just fine or at least can handle it. So it makes what we experience in the U.S. "easy" by comparison!

Scott needs to pick one!

May 9-10, 1977. Not all elevation either. 9.5" BED and 7" PVD. The 500 mb evolution was extraordinary. Giant 500 5-contour cut-off over the NEUS. Sfc low 990 mb.

That May 1967 event was epic. 10" of snow Monadnock regions. MWN 24.9" for a record May snowfall. Minor accums into central MA w/ the latest on record flakes in the air many locations, at least going back 60 years. Winds gust as high as 90 mph on the coast and ACK had over 7" of rain. May 1967 among the coldest Mays on record for the NE. BOS was -7 F for the month.

At least CoastalWx gets this consolation "prize!" Very impressive event synoptically. I'll post later on it in more details.

So Scott, did it rain so hard in Weymouth like that time when you lived in Dorchester you were concerned about house flooding?

As CoastalWx has already lamented I bet, "why couldn't we get this 3 months ago!!!" Set up synoptically is ideal for a big snowstorm, but can't fight that it is late May. Still, I bet there will be some S+ surprises in ME/NH/VT. Excellent comma head and low track w/ max dynamical cooling aloft as 500 low passes right over the region. S/w swings around the base of the mean trough and does 90 deg negative tilt w/ a W-E elliptical, oval-sharped, closed 500 low -- about as classic as it can get for "backlash."

For May 3rd this is excellent. Not often you have this kind of widespread svr wx in early May in SNE.