Alert archive / Pennsylvania / Mesoscale Discussions in 2012
Mesoscale Discussion 27
The Storm Prediction Center issued this mesoscale discussion at Jan 17, 2012, 5:37 PM EST for 10 counties in New York; 13 counties in Pennsylvania. It was in force for 113 min.
The area
The outline as issued.
The facts
- Issued
- Jan 17, 2012, 5:37 PM EST (22:37 UTC)
- Expired
- Jan 17, 2012, 7:30 PM EST
- In force
- 113 min
- Issued by
- the Storm Prediction Center
All 23 counties
Allegany County, NY, Cattaraugus County, NY, Chautauqua County, NY, Erie County, NY, Genesee County, NY, Livingston County, NY, Monroe County, NY, Ontario County, NY, Orleans County, NY, Wyoming County, NY, Armstrong County, PA, Beaver County, PA, Butler County, PA, Clarion County, PA, Crawford County, PA, Elk County, PA, Forest County, PA, Jefferson County, PA, Lawrence County, PA, McKean County, PA, Mercer County, PA, Venango County, PA, Warren County, PA
The radar
The Buffalo radar (KBUF), 101 km from the middle of the area, began a volume at 22:39 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
Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 10.6 hours before the alert went out and 100 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
- 479 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- 218 m²/s²
- 0-3 km storm-relative helicity
- 321 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
095
ACUS11 KWNS 172238
SWOMCD
SPC MCD 172237
NYZ000-PAZ000-WVZ000-OHZ000-180030-
MESOSCALE DISCUSSION 0027
NWS STORM PREDICTION CENTER NORMAN OK
0437 PM CST TUE JAN 17 2012
AREAS AFFECTED...SWRN NY...NWRN PA...E-CNTRL OH...FAR NRN PANHANDLE
OF WRN WV
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 172237Z - 180030Z
TSTMS MAY PRODUCE SVR WIND GUSTS INTO THE EVENING ACROSS WRN
NY...NWRN PA...E-CNTRL OH...AND THE FAR NRN PANHANDLE OF WRN WV.
CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE WW.
DESPITE VERY MARGINAL ELEVATED INSTABILITY ROOTED AROUND 850 MB PER
RUC SOUNDINGS...STRONG FRONTAL CONVERGENCE CONTINUES MAINTAINING A
LINE OF LOW-TOPPED SHOWERS AND TSTMS FROM NEAR ERIE PA SSWWD INTO
E-CNTRL OH. THIS ACTIVITY WILL CONTINUE TO PUSH ENEWD ACROSS PARTS
OF THE GREAT LAKES REGION INTO THE EVENING HOURS. A THREAT FOR SVR
WIND GUSTS WILL OCCUR OWING TO DOWNWARD MOMENTUM TRANSPORT IN
STRONGER CONVECTIVE ELEMENTS...WITH BUFFALO VWP DATA INDICATING
55-60 KT OF WSWLY FLOW IN THE 0.25-1-KM-AGL LAYER.
ALREADY...OBSERVED WIND GUSTS REACHING/EXCEEDING SVR CRITERIA HAVE
BEEN NOTED AROUND ASHTABULA AND CLEVELAND IN ASSOCIATION WITH THIS
ACTIVITY. FURTHERMORE...STRONG PRESSURE RISES OF 5 TO 7.5 MB PER 2
HRS HAVE BEEN NOTED ACROSS N-CNTRL OH...WITH THE ATTENDANT
ISALLOBARIC RESPONSE ALSO EXPECTED TO MAINTAIN STRONG BACKGROUND
FLOW AUGMENTING CONVECTIVELY INFLUENCED WIND GUSTS. AFTER
01Z...NOCTURNAL STABILIZATION COULD BEGIN TO MITIGATE THE SVR
POTENTIAL TO SOME DEGREE.
..COHEN.. 01/17/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BGM...BUF...CTP...PBZ...CLE...
LAT...LON 42247973 42887894 43417826 43567725 42817697 40877893
40448043 40888075 41548034 42247973Nearby
Mesoscale Discussions in Pennsylvania, 2012Mesoscale Discussions in New York, 2012Every mesoscale discussion in 2012
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.