Alert archive / Maine / Mesoscale Discussions in 2011

Mesoscale Discussion 42

January 21, 2011Penobscot County, Piscataquis County, Maine

The Storm Prediction Center issued this mesoscale discussion at Jan 21, 2011, 12:36 PM EST for Penobscot County, Piscataquis County, Maine. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jan 21, 2011, 12:36 PM EST (17:36 UTC)
Expired: Jan 21, 2011, 3:30 PM EST
In force: 3 hr
Issued by: the Storm Prediction Center

Counties Penobscot County, ME, Piscataquis County, ME

The radar

The Caribou radar (KCBW), 35 km from the middle of the area, began a volume at 17:40 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

Caribou, ME (KCAR), launched 12:00Z, 5.6 hours before the alert went out and 107 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 637 m above ground
0-6 km bulk shear: 67 kt
0-1 km storm-relative helicity: 121 m²/s²
0-3 km storm-relative helicity: 157 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

540 
ACUS11 KWNS 211736
SWOMCD
SPC MCD 211736 
MEZ000-212030-

MESOSCALE DISCUSSION 0042
NWS STORM PREDICTION CENTER NORMAN OK
1136 AM CST FRI JAN 21 2011

AREAS AFFECTED...CNTRL AND ERN MAINE

CONCERNING...HEAVY SNOW 

VALID 211736Z - 212030Z

A BAND OF HEAVY SNOW IS EXPECTED TO CONTINUE DEVELOPING DURING THE
NEXT FEW HOURS...AND LINGER THROUGH MUCH OF THE REMAINDER OF THE
AFTERNOON...IMPACTING THE INTERSTATE 95 CORRIDOR NORTHEAST OF BANGOR
WITH RATES AROUND 1 INCH PER HOUR.

IT APPEARS THAT ONGOING INTENSIFYING SNOW RATES ACROSS COASTAL AND
DOWNEAST MAINE MAY BE RELATIVELY SHORT-LIVED.  LATEST MODEL AND
OBSERVATIONAL DATA ARE SUGGESTIVE THAT MID-LEVEL SUBSIDENCE AND
DRYING WILL NOSE THROUGH THE REGION DURING THE 18-20Z TIME
FRAME...DIMINISHING HEAVIER PRECIPITATION.  MEANWHILE...AS THE
DEEPENING SURFACE CYCLONE CONTINUES TO MIGRATE NORTHEAST OF CAPE COD
TOWARD THE CANADIAN MARITIMES LATE THIS AFTERNOON AND
EVENING...FORCING WITHIN A DEVELOPING LOWER/MID TROPOSPHERIC
DEFORMATION ZONE IS EXPECTED TO PROVIDE THE FOCUS FOR A LINGERING
BAND OF HEAVY SNOW ACROSS INTERIOR MAINE.  WITH LIFT ENHANCED IN THE
FAVORABLE DENDRITIC GROWTH LAYER...CONDITIONS APPEAR SUFFICIENT TO
SUPPORT SNOW RATES AROUND OR IN EXCESS OF 1 INCH PER HOUR NEAR THE
INTERSTATE 95 CORRIDOR.  THE MOST PROLONGED HEAVIER SNOW RATES...AND
GREATEST SNOWFALL...SEEMS MOST LIKELY NORTH BANGOR...PARTICULARLY
NEAR HOULTON...WHERE SNOW COULD PERSIST BEYOND 00Z.

..KERR.. 01/21/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

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

LAT...LON   46366727 45466780 44626959 45656934 47066808 46366727

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 21, 7:32 AM EST	Mesoscale Discussion	SPC	Androscoggin, Cumberland, Hancock, Kennebec, Lincoln, Sagadahoc and 3 more	5 hr

Nearby

Mesoscale Discussions in Maine, 2011 Every mesoscale discussion in 2011

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.