811
ACUS11 KWNS 150826
SWOMCD
SPC MCD 150826
MEZ000-MAZ000-NHZ000-VTZ000-151000-

Mesoscale Discussion 1623
NWS Storm Prediction Center Norman OK
0326 AM CDT Wed Jul 15 2026

Areas affected...Parts of southern VT/NH into extreme northeast MA

Concerning...Severe Thunderstorm Watch 490...

Valid 150826Z - 151000Z

The severe weather threat for Severe Thunderstorm Watch 490
continues.

SUMMARY...An isolated hail and damaging wind threat continues early
this morning.

DISCUSSION...A pair of widely spaced supercells persist as of 0825Z
across parts of southern VT/NH. The lead supercell in southern NH
has exhibited a cycle of weakening/restrengthening over the past
hour or two. Recent VWPs from KGYX/KBOX show strong mid/upper-level
west-northwesterly flow of 60-80+ kt (around 6-9 km AGL).
Cloud-layer shear of around 40-55 kt will continue to support
updraft organization, and it is possible these supercells will track
all the way to the coast over the next couple of hours. Latest
mesoanalysis does show stronger MLCIN with southward extent into
northern MA, but this convection appears mostly elevated, with
access to a reservoir of 1500-2500 J/kg of MUCAPE. Isolated severe
hail and perhaps damaging winds remain possible in the short term
with this activity as it moves quickly east-southeastward around
45-50 kt. The lead supercell may clip part of Essex County MA, but
additional downstream watch issuance into northern MA is not
expected at this time.

..Gleason.. 07/15/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...GYX...BOX...BTV...ALY...

LAT...LON   43737316 43357168 43087073 42727074 42747116 42947205
            43297320 43737316

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN