Alert archive / Pennsylvania / Mesoscale Discussions in 2016
Mesoscale Discussion 4
The Storm Prediction Center issued this mesoscale discussion at Jan 8, 2016, 2:39 PM EST for 13 counties in New York; 15 counties in Pennsylvania. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 8, 2016, 2:39 PM EST (19:39 UTC)
- Expired
- Jan 8, 2016, 7:45 PM EST
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 28 counties
Allegany County, NY, Cattaraugus County, NY, Chautauqua County, NY, Chemung County, NY, Livingston County, NY, Ontario County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wyoming County, NY, Yates County, NY, Bradford County, PA, Cameron County, PA, Centre County, PA, Clearfield County, PA, Clinton County, PA, Elk County, PA, Forest County, PA, Jefferson County, PA, Lycoming County, PA, McKean County, PA, Potter County, PA, Sullivan County, PA, Tioga County, PA, Union County, PA, Warren County, PA
The radar
The State College radar (KCCX), 95 km from the middle of the area, began a volume at 19:39 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, 7.7 hours before the alert went out and 140 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
- 3387 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 86 m²/s²
- 0-3 km storm-relative helicity
- 117 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
406
ACUS11 KWNS 081939
SWOMCD
SPC MCD 081939
NYZ000-PAZ000-090045-
MESOSCALE DISCUSSION 0004
NWS STORM PREDICTION CENTER NORMAN OK
0139 PM CST FRI JAN 08 2016
AREAS AFFECTED...PORTIONS OF CNTRL/NRN PA AND SRN NY
CONCERNING...FREEZING RAIN
VALID 081939Z - 090045Z
SUMMARY...PRECIPITATION WILL OVERSPREAD THE AREA LATER THIS
AFTERNOON INTO THE EARLY EVENING. AREAS OF FREEZING RAIN WITH RATES
OF 0.05 INCH PER 3 HOURS WILL BE POSSIBLE INTO THE EVENING HOURS.
DISCUSSION...MOSAIC RADAR IMAGERY AND SFC OBSERVATIONS INDICATE A
SHIELD OF PRECIPITATION EXTENDING FROM LOWER MI SEWD ACROSS LAKE
ERIE TO THE UPPER OHIO VALLEY...SPREADING NEWD. THIS ACTIVITY IS IN
ASSOCIATION WITH A PLUME OF LOW-LEVEL WARM ADVECTION PRECEDING
ILL-PHASED SHORTWAVE TROUGHS EXTENDING FROM THE MID-MS VALLEY TO THE
MID-ATLANTIC. DESPITE NEAR/ABOVE-FREEZING SFC TEMPERATURES IN MANY
AREAS ACROSS THE REGION...DEWPOINTS IN THE TEENS AND 20S SUGGEST
THAT WET-BULB COOLING WILL OCCUR. GIVEN WET-BULB SFC TEMPERATURES
BELOW 32F...THE POTENTIAL FOR FREEZING RAIN WILL EXIST AS LOW-LEVEL
SATURATION OCCURS BEHIND THE LEADING EDGE OF THE PRECIPITATION-
RELATED REFLECTIVITY SHIELD. THE POTENTIAL FOR FREEZING RAIN WILL
MOST LIKELY SPREAD ACROSS THE REGION IN THE 21Z-01Z TIME FRAME...AND
CONTINUE INTO THE EVENING HOURS. WHILE WARMING OF THE LOW-LEVEL
THERMAL PROFILE IS EXPECTED IN THE WARM-ADVECTION PATTERN...SUCH
WARMING WILL BE OFFSET BY INITIAL EVAPORATION-RELATED COOLING TO
KEEP SFC TEMPERATURES BELOW 32F IN MANY AREAS -- PARTICULARLY IN
SHELTERED VALLEYS -- INTO THE EVENING HOURS. PRECIPITATION WILL
GENERALLY BE LIGHT...WITH FREEZING-RAIN RATES OF 0.05 INCH PER 3
HOURS POSSIBLE.
..COHEN.. 01/08/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BGM...BUF...CTP...PBZ...CLE...
LAT...LON 41227933 41647982 42147981 42727888 42957774 42777640
42477598 41607601 41077676 40777754 40777838 41227933Nearby
Mesoscale Discussions in Pennsylvania, 2016Mesoscale Discussions in New York, 2016Every mesoscale discussion in 2016
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.