Severe Storm Outlook Narrative (AC)
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ACUS11 KWNS 171710
SWOMCD
SPC MCD 171709
MEZ000-NHZ000-VTZ000-NYZ000-171945-
Mesoscale Discussion 1698
NWS Storm Prediction Center Norman OK
1209 PM CDT Thu Jul 17 2025
Areas affected...VT...NH...ME
Concerning...Severe potential...Watch likely
Valid 171709Z - 171945Z
Probability of Watch Issuance...80 percent
SUMMARY...Increasing thunderstorm coverage and intensity is
anticipated across New England this afternoon and evening.
Environmental conditions will support potential severe thunderstorms
capable of damaging wind gusts and perhaps a tornado or two.
DISCUSSION...Visible satellite imagery continues to show deepening
cumulus within the broad warm sector in place across much of New
England this afternoon. This deepening is fostered by a combination
of strengthening ascent and diurnal destabilization. The airmass
across the region is very moist, with dewpoints in the low 70s and
PW values around 2 inches. Expectation is for both continued
destabilization and persistent forcing for ascent to result in the
development of scattered to numerous thunderstorms. Mid-level flow
is forecast to strengthen throughout the day as a low-amplitude
shortwave trough moves through southern ON and QC.
The resulting combination of buoyancy and shear should support
transient supercell structures across much of the region,
particularly across ME where the mid-level flow will be the
strongest. Damaging gusts will be the primary risk with most of
these storms. More southerly surface winds are anticipated across ME
as well, strengthening the low-level shear and enhancing the tornado
potential with any more persistent updrafts. Overall severe coverage
will likely be high enough to merit watch issuance.
..Mosier/Smith.. 07/17/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CAR...GYX...BTV...ALY...
LAT...LON 47296949 47456858 47186781 46506780 45526843 42847105
43047321 43997363 45007321 45137173 45337099 45977038
47296949
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH