Alert archive / Massachusetts / Tornado Watches in 2018
Tornado Watch 96
The Storm Prediction Center issued this tornado watch at May 15, 2018, 2:23 PM EDT for Capitol Planning Region, Northeastern Connecticut Planning Region, Connecticut; 4 counties in Massachusetts. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- May 15, 2018, 2:23 PM EDT (18:23 UTC)
- Expired
- May 15, 2018, 6:21 PM EDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 65 kt
Counties Capitol Planning Region, CT, Northeastern Connecticut Planning Region, CT, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Worcester County, MA
The radar
The Boston radar (KBOX), 116 km from the middle of the area, began a volume at 18:24 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 90%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 3:06 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 54 min |
| May 15, 3:13 PM EDT | Severe Thunderstorm Warning | BOX | Franklin, Hampshire | 47 min |
| May 15, 3:33 PM EDT | Severe Thunderstorm Warning | BOX | Franklin, Hampshire, Worcester | 42 min |
| May 15, 3:36 PM EDT | Tornado Warning | BOX | Capitol Planning Region | 24 min |
| May 15, 3:46 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 59 min |
| May 15, 4:02 PM EDT | Tornado Warning | BOX | Capitol Planning Region | 28 min |
| May 15, 4:42 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region, Northeastern Connecticut Planning Region | 63 min |
| May 15, 4:59 PM EDT | Severe Thunderstorm Warning | BOX | Middlesex, Suffolk, Worcester | 31 min |
| May 15, 5:48 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 27 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Albany, NY (KALY), launched 12:00Z, 6.4 hours before the alert went out and 120 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 932 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 103 m²/s²
- 0-3 km storm-relative helicity
- 259 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
922
WWUS20 KWNS 151820
SEL6
SPC WW 151820
CTZ000-MAZ000-160100-
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 96
NWS Storm Prediction Center Norman OK
225 PM EDT Tue May 15 2018
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Northern Connecticut
Western and central Massachusetts
* Effective this Tuesday afternoon and evening from 225 PM until
900 PM EDT.
* Primary threats include...
A couple tornadoes possible
Widespread damaging winds likely with isolated significant gusts
to 75 mph possible
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
SUMMARY...A tornado risk may develop east from the Hudson Valley
into parts of southern New England this afternoon with discrete
cells ahead of a fast-moving squall line. Widespread damaging winds
are anticipated with the squall line.
The tornado watch area is approximately along and 35 statute miles
north and south of a line from 10 miles northwest of Westfield MA to
5 miles south southeast of Worcester MA. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
WOU6).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 93...WW 94...WW 95...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2 inches. Extreme turbulence and surface wind
gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 27040.
...GramsSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 11:43 AM EDT | Mesoscale Discussion | SPC | 3 hr | |
| May 15, 1:03 PM EDT | Tornado Watch | SPC | Northwest Hills Planning Region | 4 hr |
| May 15, 1:46 PM EDT | Severe Thunderstorm Watch | SPC | Greater Bridgeport Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region, Southeastern Connecticut Planning Region | 9 hr |
| May 15, 1:58 PM EDT | Mesoscale Discussion | SPC | 2 hr | |
| May 15, 2:38 PM EDT | Mesoscale Discussion | SPC | 2 hr | |
| May 15, 3:33 PM EDT | Mesoscale Discussion | SPC | 117 min | |
| May 15, 2:26 PM EDT | Severe Thunderstorm Watch | SPC | Bristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk | 5 hr |
Nearby
Tornado Watches in Massachusetts, 2018Tornado Watches in Connecticut, 2018Every tornado watch in 2018
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.