Severe Storm Outlook Narrative (AC)
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
ACUS11 KWNS 122118
SWOMCD
SPC MCD 122117
NYZ000-NJZ000-PAZ000-DEZ000-MDZ000-VAZ000-WVZ000-122245-

Mesoscale Discussion 1480
NWS Storm Prediction Center Norman OK
0417 PM CDT Sat Aug 12 2017

Areas affected...Central/Eastern NY...Eastern PA...Central MD...Far
Northeast VA

Concerning...Severe Thunderstorm Watch 447...448...

Valid 122117Z - 122245Z

The severe weather threat for Severe Thunderstorm Watch 447, 448
continues.

SUMMARY...Threat for damaging wind gusts and hail continues across
central/eastern NY as well as across southeastern PA and central MD.

DISCUSSION...Two separate areas of relatively higher thunderstorm
coverage have evolved over the region covered by WW 447 and 448.
Storms across the more northern area (over central NY) have shown
transient supercell structures and have produced isolated severe
hail as well as damaging wind gusts. Surface analysis places the
cold front from just east of RME southwestward through ELM.
Continued eastward progression of this front will impinge upon the
remaining instability across eastern NY, limiting the spatial extend
of potential severe storms. Even so, threat for isolated severe
thunderstorms will remain for the next few hours. Primary severe
threat is damaging wind gusts, although some hail is possible within
the stronger updrafts resulting from new development and/or storm
mergers.

Separate area of thunderstorms across southeast PA and adjacent
central MD is a bit more linear than those farther north, likely a
result of closer storm proximity, more moist storm inflow, and cold
pool amalgamation. Given the favorable downstream airmass, threat
for damaging wind gusts and hail will persist within this line of
storms as it continues southeastward for the next few hours.

..Mosier.. 08/12/2017

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

ATTN...WFO...OKX...ALY...PHI...BGM...CTP...LWX...

LAT...LON   42097679 43207569 43697461 43127351 39257575 39227828
            42097679




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.