Oct 7, 2020 0600 UTC Day 1 Convective Outlook
Updated: Wed Oct 7 05:41:40 UTC 2020 (20201007 1200Z Day 1 shapefile | 20201007 1200Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20201007 1200 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 82,007 16,635,670 Boston, MA...Rochester, NY...Providence, RI...Worcester, MA...Springfield, MA...
Probabilistic Tornado Graphic
20201007 1200 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20201007 1200 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 82,042 16,649,674 Boston, MA...Buffalo, NY...Rochester, NY...Providence, RI...Worcester, MA...
Probabilistic Large Hail Graphic
20201007 1200 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 070541

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1241 AM CDT Wed Oct 07 2020

   Valid 071200Z - 081200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NEW YORK TO
   NEW ENGLAND...

   ...SUMMARY...
   Gusty winds are possible with thunderstorms later today from New
   York into New England.

   ...NY to New England...

   Strong mid-level short-wave trough is currently digging southeast
   across the Great Lakes. This feature is forecast to progress into NY
   early in the period before ejecting off the New England coast by
   08/00z. Latest model guidance suggests 120-150m mid-level height
   falls and pronounced high-level difluence will spread across the
   northeastern US during daylight hours. This strongly-forced system
   will encourage scattered low-topped convection along/ahead of a cold
   front as it surges across NY during the late morning hours. While
   boundary-layer moisture is not forecast to be that significant, and
   overall moisture is somewhat meager, steep low-level lapse rates and
   cooling profiles strongly favor surface-based convection, especially
   along the front where convergence will be maximized. Latest CAMs
   support this scenario with a band of weak elevated convection
   expected to spread ahead of the front early, then isolated-scattered
   convection developing ahead of the front where partial sunshine and
   surface thermals will be maximized. 

   Given the increasing westerly flow in the cloud-bearing layer, there
   is some concern for stronger winds mixing to the surface; however,
   weak buoyancy could limit this mixing. Will maintain 5 percent
   severe probabilities for gusty winds primarily due to
   buoyancy/updraft concerns. If it becomes more clear that robust
   convection will be more concentrated then severe probabilities may
   be adjusted accordingly. Severe threat should spread across New
   England during the afternoon and off the Atlantic Coast by early
   evening.

   ..Darrow/Squitieri.. 10/07/2020

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z