Oct 30, 2021 1630 UTC Day 1 Convective Outlook
Updated: Sat Oct 30 16:12:44 UTC 2021 (20211030 1630Z Day 1 shapefile | 20211030 1630Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20211030 1630 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 4,496 2,496,135 Boston, MA...Brockton, MA...Plymouth, MA...Lynn, MA...Quincy, MA...
Probabilistic Tornado Graphic
20211030 1630 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
20211030 1630 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 % 4,442 2,325,428 Boston, MA...Brockton, MA...Plymouth, MA...Lynn, MA...Quincy, MA...
Probabilistic Large Hail Graphic
20211030 1630 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 301612

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1112 AM CDT Sat Oct 30 2021

   Valid 301630Z - 311200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
   AND EVENING OVER EASTERN MASSACHUSETTS....

   ...SUMMARY...
   Thunderstorms with gusty winds may affect eastern Massachusetts this
   afternoon and early evening.

   ...New England...
   A vigorous shortwave trough is currently along the Carolina coast. 
   This system will track northward, with an associated deepening
   surface low approaching the coast of southeast New England later
   this afternoon and early evening.  It currently appears the low will
   move into RI or eastern MA, with very strong southeasterly low-level
   winds in the warm sector over Cape Cod.  This may be coincident with
   a cluster of thunderstorms indicated by several CAM solutions. 
   Forecast soundings suggest the near-ground stable layer will be
   rather shallow, with the potential for isolated strong/severe gusts
   in the most organized cells.  It appears this threat will primarily
   be during the 21-03z period.

   ..Hart.. 10/30/2021

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z