Alert archive / Maine / Mesoscale Discussions in 2010
Mesoscale Discussion 2139
The Storm Prediction Center issued this mesoscale discussion at Dec 26, 2010, 8:38 PM EST for 11 counties in Maine; 10 counties in New Hampshire. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 26, 2010, 8:38 PM EST (01:38 UTC)
- Expired
- Dec 27, 2010, 2:45 AM EST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
All 21 counties
Androscoggin County, ME, Cumberland County, ME, Franklin County, ME, Hancock County, ME, Kennebec County, ME, Oxford County, ME, Penobscot County, ME, Sagadahoc County, ME, Waldo County, ME, Washington County, ME, York County, ME, Belknap County, NH, Carroll County, NH, Cheshire County, NH, Coos County, NH, Grafton County, NH, Hillsborough County, NH, Merrimack County, NH, Rockingham County, NH, Strafford County, NH, Sullivan County, NH
The radar
The Portland,ME radar (KGYX), 58 km from the middle of the area, began a volume at 01:41 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 00:00Z, 1.6 hours before the alert went out and 59 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
- 617 m above ground
- 0-6 km bulk shear
- 78 kt
- 0-1 km storm-relative helicity
- 275 m²/s²
- 0-3 km storm-relative helicity
- 287 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
599
ACUS11 KWNS 270139
SWOMCD
SPC MCD 270138
MEZ000-MAZ000-NHZ000-VTZ000-270745-
MESOSCALE DISCUSSION 2139
NWS STORM PREDICTION CENTER NORMAN OK
0738 PM CST SUN DEC 26 2010
AREAS AFFECTED...SRN HALF OF ME...MUCH OF NH
CONCERNING...HEAVY SNOW
VALID 270138Z - 270745Z
SNOWFALL RATES /UP TO 1 IN PER HR/ ARE FORECAST TO INCREASE THROUGH
09Z ACROSS THE SRN HALF OF ME AND MUCH OF NH. WIND GUSTS WILL ALSO
INCREASE DURING THIS TIME...LEADING TO BLOWING SNOW AND REDUCED
VISIBILITY.
INTENSE CYCLONE LIFTING NWD TOWARD NEW ENGLAND IS FORECAST TO
OCCLUDE OVER NIGHT...WHICH WILL CAUSE THE CYCLONICALLY CURVED BRANCH
OF THE WARM CONVEYOR BELT TO WRAP SEWD ACROSS ME AND SWD THROUGH
ERN/SERN NY. AS THIS OCCURS...INTENSE ISENTROPIC UPGLIDE...WHICH IS
CURRENTLY FORCING A PLUME OF OFFSHORE PRECIPITATION...WILL SHIFT NWD
ACROSS THE SRN HALF OF ME AND MUCH OF NH. DEEP SATURATED ISOTHERMAL
LAYER THROUGH 700 MB IS OBSERVED IN 00Z RAOBS AND MODEL FORECAST
SOUNDINGS...AND THEN TRANSITIONS TO A STEEP MIDLEVEL LAPSE RATE
ENVIRONMENT THAT IS EXPECTED TO SUPPORT WEAK CONVECTIVE INSTABILITY
WITH TIME. THE COMBINATION OF STRENGTHENING ISENTROPIC ASCENT AND
WEAK STABILITY WILL FAVOR SNOWFALL RATES UP TO 1 IN/HR...WHICH WILL
SPREAD NWD OUT OF SRN NH/COASTAL ME INTO CNTRL/NRN NH AND CNTRL ME
THROUGH 09Z.
..GARNER.. 12/27/2010
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CAR...GYX...BOX...BTV...
LAT...LON 45217076 45796896 45856766 45406724 44846704 44556766
44356871 43906974 43407039 42877086 42717155 42767245
43537235 44567167 45217076SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 27, 3:30 AM EST | Mesoscale Discussion | SPC | Androscoggin, Franklin, Kennebec, Oxford, Penobscot, Waldo | 4 hr |
Nearby
Mesoscale Discussions in Maine, 2010Mesoscale Discussions in New Hampshire, 2010Every mesoscale discussion in 2010
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.