An unseasonably hot and humid airmass moved into the region allowing for instability values more typical for summer. In addition, a pre-frontal trough approached New Hampshire ahead of the main surface cold front located to the west in Quebec Province.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GYX wrote it up.
An unseasonably hot and humid airmass moved into the region allowing for instability values more typical for summer. In addition, a pre-frontal trough approached New Hampshire ahead of the main surface cold front located to the west in Quebec Province. A strong jet streak aloft allowed for strong 0-6sm shear profiles. These ingredients led to organized linear convection by the afternoon hours with numerous reports of straight line wind damage across the state.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Gray, ME wrote its last area forecast discussion before the first event at May 26, 3:58 PM EST, 22 minutes earlier.
Area Forecast Discussion National Weather Service Gray ME 458 PM EDT Wed May 26 2021 .SYNOPSIS... A cold front will cross the region this evening. This front will bring a threat of severe thunderstorms through the early evening hours. High pressure will build north of the region Thursday and Friday, as low pressure passes through the mid- Atlantic states to our south. This low will bring a chance of showers to southern areas, mainly Friday afternoon and evening. Low pressure may affect the region around Monday with some rainy weather. && .NEAR TERM /THROUGH TONIGHT/... 5PM UPDATE... Made some adjustments to temperatures and precipitation chances based on latest observations and radar trends. Generally we are expecting a line of storms tracking across the area over the next few hours. This will be our primary window for severe weather including damaging wind gusts. ORIGINAL DISCUSSION... Impacts: Showers and thunderstorms, some of which will be severe, are expected to affect the region from now through the late evening. Damaging winds are the primary threat, but an isolated tornado and hail cannot be ruled out. Still rather quiet across the CWA at the moment with only some showers moving across northern areas. A line of showers and thunderstorms currently stretches from upstate NY into eastern PA with the southern half of the line being the most active. Overall, not a whole lot of change in forecast thinking from this morning. The line of showers and thunderstorms will continue to push east through this evening with some individual cells possibly developing ahead of it. Stronger storms within the line will be capable of producing damaging winds as they move across the CWA. In fact, based on recent mesoanalysis, there may be more downdraft CAPE than regular CAPE in many areas right now and this may be the case going forward too with steep low-level lapse rates. The changes to forecast thinking are mostly subtle, primarily influenced from recent mesoanalysis and the 18Z ALY sounding. Small hail remains a threat, but with poor mid-level lapse rates and a freezing level well above 10000 ft from the ALY sounding, likely not a high chance for any hail. Dew points have been dropping since this morning with most of our automated sites in the upper 50s to lower 60s...and the 18Z ALY sounding had LCLs well above 1500 meters. While there is still a nonzero chance for an isolated tornado, the threat is much lower than this morning. In coordination with SPC, a Severe Thunderstorm Watch has been issued for all of NH and the westernmost ME counties, including Cumberland County, that is in effect through 11pm EDT. Once the showers and thunderstorms exit the region late this evening, cooler and drier air will begin to filter into the region behind a cold front. Lows will range from the lower 50s to mid 60s. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... Impacts: Minimal. Possible fire weather concerns on Thursday. Possible frost concerns for northern areas Thursday night. High pressure begins to build into the region on Thursday with cooler and drier air continuing to filter into the region. Sunny skies are expected as highs range from the upper 50s in the mountains to the upper 70s in southern areas. Breezy northwest winds may ultimately produce elevated fire conditions for portions of the region Thursday afternoon. High pressure continues to build into the region Thursday night, though clouds will be on the increase. Lows will be quite cool, ranging from the mid 30s north to the upper 40s. Will see how much cloud cover is present, but will need to monitor for possible frost for northern areas Thursday night with light winds expected. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... The main headline in the extended portion of the forecast will be much cooler temperatures than we are seeing today, and in some instances, possibly well below normal. The models are in reasonable agreement that low pressure will move off the Mid Atlantic Coast Friday into Friday night. Enough forcing for ascent and moisture advection looks to be in place north of the low for some rain across southern zones, mainly southern NH, centered around Friday afternoon and Friday night. Otherwise, the air mass in place over northern New England will be quite dry. If clouds stay away from the mountain zones Friday night, there could be a frost. The main period of uncertainty in this extended is what will the sensible weather be on Memorial Day. There are several solutions on the table including a low probability of a soaking rain as per the 00z ECMWF. There are some ensemble members that support this solution but it's an outlier. Will go with chance PoPs since in most cases there's an upper level low around. Otherwise, temperatures will remain near to below normal, with the potential for well below normal if a more rainier pattern looks to take place early in the week. Dry weather looks to be the case Tue-Wed. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Short Term...Showers and thunderstorms will move through the region late this afternoon and this evening, clearing the region late this evening. Northwest winds arrive behind a cold front early tomorrow morning and continue through the day on Thursday. Light winds and VFR conditions expected Thursday night. Long Term...Possible MVFR conditions Friday afternoon and night across southernmost NH in showers but right now prevailing VFR looks to be a better bet. Otherwise, VFR Thursday night and also Saturday, Sunday. && .MARINE... Short Term...SCA remains in effect through early Thursday morning, but winds and seas should remain below SCA criteria through the remainder of the period. Showers and possibly a thunderstorm expected over the waters this evening and early tonight with a shift to northwest winds on Thursday. Long Term...SCA conditions, mainly for seas, will be possible Sunday through Monday night in association with a long fetch of northeast winds. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 6 AM EDT Thursday for ANZ150>154. && NEAR TERM...Watson SHORT TERM...Watson LONG TERM...Ekster
Hazardous Weather Outlook National Weather Service Gray ME 407 PM EDT Wed May 26 2021 MEZ007-012-018-019-023-024-033-NHZ001>015-272015- Northern Oxford-Southern Oxford-Interior York- Central Interior Cumberland-Coastal York-Coastal Cumberland- Interior Cumberland Highlands-Northern Coos-Southern Coos- Northern Grafton-Northern Carroll-Southern Grafton-Southern Carroll- Sullivan-Merrimack-Belknap-Strafford-Cheshire-Eastern Hillsborough- Interior Rockingham-Coastal Rockingham- Western And Central Hillsborough- 407 PM EDT Wed May 26 2021 ...SEVERE THUNDERSTORM WATCH 208 IN EFFECT UNTIL 11 PM EDT THIS EVENING... This Hazardous Weather Outlook is for Maine, southwest Maine, western Maine, New Hampshire, central New Hampshire, northern New Hampshire and southern New Hampshire. .DAY ONE...Tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Severe Thunderstorm Watch. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation will likely be needed. MEZ008-009-013-014-020>022-025>028-272015- Northern Franklin-Central Somerset-Southern Franklin- Southern Somerset-Androscoggin-Kennebec-Interior Waldo-Sagadahoc- Lincoln-Knox-Coastal Waldo- 407 PM EDT Wed May 26 2021 This Hazardous Weather Outlook is for south central Maine, southwest Maine, west central Maine and western Maine. .DAY ONE...Tonight. A few thunderstorms are possible through this evening. Although widespread severe weather is not expected, a few storms could producing damaging winds and large hail. An isolated tornado is possible. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation will likely be needed. ANZ150>154-272015- Coastal Waters from Stonington, ME to Port Clyde, ME out 25 NM- Penobscot Bay- Coastal Waters from Port Clyde, ME to Cape Elizabeth, ME out 25 NM- Casco Bay- Coastal Waters from Cape Elizabeth, ME to Merrimack River, MA out 25 NM- 407 PM EDT Wed May 26 2021 This Hazardous Weather Outlook is for Atlantic coastal waters. .DAY ONE...Tonight. Thunderstorms will approach the coast this evening. Some storms could produce damaging winds and large hail especially near the coast. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to Standard Operating Procedures.
Special Weather Statement
National Weather Service Gray ME
446 PM EDT Wed May 26 2021
NHZ003-005-262115-
Northern Grafton-Southern Grafton-
446 PM EDT Wed May 26 2021
...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN GRAFTON COUNTY...
At 445 PM EDT, a strong thunderstorm was located over Norwich, or 7
miles north of White River Junction, moving east at 40 mph.
Winds in excess of 40 mph are possible with this storm.
Locations impacted include...
Lebanon, Plymouth, Hanover, Canaan, Groton, Piermont, Lyme, Hebron,
Dorchester, Ellsworth, Wentworth, Rumney, Orford and Orange.
If outdoors, consider seeking shelter inside a building.
LAT...LON 4370 7230 4373 7226 4377 7220 4379 7220
4381 7218 4382 7219 4383 7218 4386 7219
4387 7217 4389 7217 4398 7181 4372 7171
4365 7231
TIME...MOT...LOC 2045Z 255DEG 33KT 4376 7230
ClairSpecial Weather Statement
National Weather Service Gray ME
459 PM EDT Wed May 26 2021
MEZ007-NHZ001-262145-
Northern Oxford-Northern Coos-
459 PM EDT Wed May 26 2021
...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN OXFORD AND
NORTHEASTERN COOS COUNTIES...
At 459 PM EDT, a strong thunderstorm was located near Canaan, or 13
miles northwest of Colebrook, moving northeast at 45 mph.
Winds in excess of 40 mph and half inch hail are possible with this
storm.
Locations impacted include...
Pittsburg, Clarksville, Oxbow, Lynchtown, Parmachenee, Bowmantown,
Stewartstown and Upper Cupsuptic.
If outdoors, consider seeking shelter inside a building.
LAT...LON 4531 7092 4524 7090 4523 7086 4514 7093
4499 7151 4498 7154 4501 7147 4501 7150
4507 7150 4512 7143 4520 7140 4524 7144
4523 7138 4527 7136 4530 7130 4525 7123
4524 7113 4530 7110 4532 7100 4535 7101
TIME...MOT...LOC 2059Z 244DEG 47KT 4507 7161
ClairThe Burlington radar (KCXX), 111 km away, was scanning. The volume nearest the first event began at 21:20 UTC.
18 thunderstorm wind. Local standard time, as filed.
A severe thunderstorm downed multiple trees off of Highway 302 in Littleton.
A severe thunderstorm downed multiple trees in Cornish.
A severe thunderstorm downed multiple trees that brought down wires on Ball Park Rd. in Goshten.
A severe thunderstorm downed multiple trees that brought town utility wires in Claremont.
A severe thunderstorm downed multiple trees and large branches with scattered debris across Highway 32 near South Rd. in East Swanzey.
A severe thunderstorm downed multiple trees in Newport.
A severe thunderstorm downed multiple trees in Stoddard.
A severe thunderstorm downed multiple trees that brought down utility wires in Bristol.
A severe thunderstorm downed multiple trees and branches in East Sandwich.
A severe thunderstorm downed multiple trees that brought down wires in Warner.
A severe thunderstorm downed multiple trees that brought down utility wires in Andover.
A severe thunderstorm downed multiple tress which brought down wires on Bryant and Proctor Rd. in Jaffrey.
A severe thunderstorm downed a large tree that blocked Tannery Hill Rd and Middle Hancock Rd.
A severe thunderstorm downed multiple trees that brought down wires in Glendale near Lake Shore Rd.
A severe thunderstorm downed multiple trees that brought down utility wires in Laconia.
A personal weather station measured a gust of 60 mph in West Alton.
A severe thunderstorm downed multiple trees that brought down utility wires in lower Hillsboro village.
A severe thunderstorm downed multiple trees on Nutes Rd. in Milton.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in New Hampshire in 2021Every state in 2021This day in weather historyWarnings in New Hampshire, May 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 963018, 963017, 963005, 963015, 963016, 963014, 963013, 963006, 963007, 963022, 963008, 963012, 963021, 963020, 963009, 963010, 963019, 963011.