Alert archive / Maine / Mesoscale Discussions in 2024

Mesoscale Discussion 913

May 23, 20248 counties in Maine

The Storm Prediction Center issued this mesoscale discussion at May 23, 2024, 3:29 PM EDT for 8 counties in Maine. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
May 23, 2024, 3:29 PM EDT (19:29 UTC)
Expired
May 23, 2024, 5:00 PM EDT
In force
91 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 292

Counties Androscoggin County, ME, Hancock County, ME, Kennebec County, ME, Knox County, ME, Lincoln County, ME, Penobscot County, ME, Sagadahoc County, ME, Waldo County, ME

The radar

The Caribou radar (KCBW), 133 km from the middle of the area, began a volume at 19:29 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.

The nearest sounding before it

Gray, ME (KGYX), launched 12:00Z, 7.5 hours before the alert went out and 174 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.

Skew-T log-pSkew-T log-p diagram, Gray, ME at 12:00Z on 2024-05-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 434 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Gray, ME at 12:00Z on 2024-05-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
434 J/kg
Mixed-layer CIN
-131 J/kg
Mixed-layer LCL
1469 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
66 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

701 
ACUS11 KWNS 231929
SWOMCD
SPC MCD 231929 
MEZ000-232100-

Mesoscale Discussion 0913
NWS Storm Prediction Center Norman OK
0229 PM CDT Thu May 23 2024

Areas affected...Parts of southern/eastern ME

Concerning...Severe Thunderstorm Watch 292...

Valid 231929Z - 232100Z

The severe weather threat for Severe Thunderstorm Watch 292
continues.

SUMMARY...Some threat for hail and damaging wind will spread
eastward through the afternoon.

DISCUSSION...A line of strong to potentially severe thunderstorms is
ongoing from southern into northeast Maine this afternoon. The
immediate downstream environment remains somewhat favorable for
organized convection, with MLCAPE approaching 1000 J/kg and modestly
favorable deep-layer shear (as noted on the 17Z/18Z CAR/GYX modified
soundings and regional VWPs), and some threat for hail and damaging
wind will continue into late afternoon. 

With cooler onshore flow noted over the Downeast Maine vicinity,
some weakening will be possible with time as storms move into this
region. However, sufficient elevated buoyancy may still support some
threat for isolated marginal hail and/or a strong/damaging gust
before storms move offshore. Isolated storm redevelopment also
remains possible into southern ME behind the outflow, though at this
time any severe threat with this redevelopment is currently expected
to remain marginal and isolated.

..Dean.. 05/23/2024

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

ATTN...WFO...CAR...GYX...

LAT...LON   44466996 45846876 47016855 47236857 47266808 46866769
            45846764 44756782 44256824 43856895 43756954 43796993
            43927026 44177063 44466996

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 23, 12:03 PM EDTMesoscale DiscussionSPCAndroscoggin, Franklin, Kennebec, Oxford, Penobscot, Piscataquis and 1 more117 min
May 23, 12:48 PM EDTSevere Thunderstorm WatchSPCAndroscoggin, Aroostook, Franklin, Hancock, Kennebec, Knox and 8 more4 hr

Nearby

Mesoscale Discussions in Maine, 2024Every mesoscale discussion in 2024

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.