Severe Weather Coordination Message #2 – Tuesday PM & Evening 7/21/26 & Wednesday PM & Evening 7/22/26 Severe Weather & Flash Flood Potential
Hello to all…
..A warm front followed by a strong pre-frontal trough and then a cold front will approach Southern New England late Tuesday Morning through Wednesday evening setting the stage for potentially two or perhaps three rounds of isolated to scattered strong to severe thunderstorms one late Tuesday AM into mid-Tuesday Afternoon which is the most conditional and weaker potential, a second round Tuesday Evening through the overnight hours into early Wednesday Morning with a third round of severe weather potential Wednesday PM and Evening. Much of Southern New England has severe weather potential but the greatest risk is over Western and Central Massachusetts, Connecticut, Rhode Island and into South Coastal Massachusetts Tuesday PM through early Wednesday AM while all of New England has a marginal risk Wednesday PM and Evening..
..The Storm Prediction Center (SPC) has a Marginal risk for severe weather Tuesday Afternoon through early Wednesday AM across Western and Central Massachusetts, Connecticut and Rhode Island. Threat potential timeframe is between 4 PM Tuesday through 4 AM Wednesday though we will need to monitor activity along the warm front late Tuesday AM into mid-afternoon Tuesday for a more conditional lower risk threat of severe weather. The Storm Prediction Center (SPC) also has all of Southern New England in a marginal risk for severe weather for Wednesday Afternoon and Evening. Strong to damaging winds, hail, frequent lightning and heavy downpours leading to urban and poor drainage flooding are the primary risks but even an isolated tornado cannot be ruled out..
..In addition, a High Surf Advisory is in effect from 6 AM Wednesday to 8 PM Thursday for Cape Cod and the Islands, Washington, Newport Counties of Rhode Island, Southern Plymouth and Southern Bristol Counties of Massachusetts for dangerous surf and rip current conditions..
..SKYWARN Self-Activation with Amateur Radio Call-Up Nets are possible late Tuesday Morning through early Wednesday AM and again Wednesday Afternoon and Evening based on the severe weather and flash flood potential. Pictures and videos of wind damage, hail, flooding etc. can be sent as a reply to this email, via our Facebook/X/Bluesky feeds or the email address pics@nsradio.org with credit given to the spotter unless otherwise indicated..
Active couple days for severe weather and flash flood potential. The headlines depict the current thinking. Key factors include:
Tuesday Key Factors:
1.) A warm front is pushing through the region and while this warm front is less likely to produce severe weather, there is one severe thunderstorm warning in Southeast NY as of 1030 AM and there is an isolated risk for a strong or severe thunderstorm with the warm front as it moves through the area and will bear watching.
2.) Clearing to allow for destabilization ahead of the pre-frontal trough to allow for instability for severe weather potential into later Tuesday Evening. Shear profiles are sufficiently strong enough to produce severe weather.
3.) Strong wind shear being able to compensate for limited instability and timing of the pre-frontal trough past peak heating into the evening and overnight hours.
Wednesday Key Factors:
1.) Wind shear will remain sufficiently strong for severe weather but instability is in question depending on clearing to allow for destabilization.
2.) Wind shear and its ability to compensate for limited instability if that occurs.
3.) Timing of the cold front through New England which is currently expected to be favorable in the mid to late afternoon and early evening.
SKYWARN Self-Activation with Amateur Radio Call-Up Nets are possible late Tuesday Morning through early Wednesday AM and again Wednesday Afternoon and Evening based on the severe weather and flash flood potential. Pictures and videos of wind damage, hail, flooding etc. can be sent as a reply to this email, via our Facebook/X/Bluesky feeds or the email address pics@nsradio.org with credit given to the spotter unless otherwise indicated. Another coordination message will be posted either by 11 PM Tuesday Evening or 11 AM Wednesday Morning depending upon activity Tuesday Evening. Below is the NWS Boston/Norton High Surf Advisory Statement, Area Forecast Discussion, Enhanced Hazardous Weather Outlook and SPC Day-1 & Day-2 Outlooks..
NWS Boston/Norton High Surf Advisory Statement:
https://forecast.weather.gov/product.php?site=NWS&issuedby=BOX&product=CFW&format=CI&version=1&glossary=1&highlight=off
NWS Boston/Norton Area Forecast Discussion:
https://forecast.weather.gov/product.php?site=NWS&issuedby=BOX&product=AFD&format=CI&version=1&glossary=1&highlight=off
NWS Boston/Norton Enhanced Hazardous Weather Outlook:
https://www.weather.gov/erh/ghwo?wfo=box
SPC Day-1 Convective Outlook:
https://www.spc.noaa.gov/products/outlook/day1otlk.html
SPC Day-2 Convective Outlook:
https://www.spc.noaa.gov/products/outlook/day2otlk.html
Respectfully Submitted,
Robert Macedo (KD1CY)
ARES SKYWARN Coordinator
Eastern Massachusetts ARES Section Emergency Coordinator
Home Phone #: (508) 994-1875
Home/Data #: (508) 997-4503
Email Address: rmacedo@rcn.com
https://ares.ema.arrl.org
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