Alert archive / Pennsylvania / Mesoscale Discussions in 2004
Mesoscale Discussion 69
The Storm Prediction Center issued this mesoscale discussion at Feb 3, 2004, 4:28 AM EST for 5 states. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 3, 2004, 4:28 AM EST (09:28 UTC)
- Expired
- Feb 3, 2004, 7:30 AM EST
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
All 80 counties
Allegany County, MD, Frederick County, MD, Garrett County, MD, Washington County, MD, Chemung County, NY, Allegheny County, PA, Armstrong County, PA, Bedford County, PA, Blair County, PA, Bradford County, PA, Butler County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Elk County, PA, Fayette County, PA, Forest County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Lycoming County, PA, McKean County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Potter County, PA, Snyder County, PA, Somerset County, PA, Sullivan County, PA, Tioga County, PA, Union County, PA, Westmoreland County, PA, Albemarle County, VA, Amherst County, VA, Augusta County, VA, Bath County, VA, Botetourt County, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fauquier County, VA, Frederick County, VA, Greene County, VA, Highland County, VA, Loudoun County, VA, Madison County, VA, Nelson County, VA, Page County, VA, Rappahannock County, VA, Rockbridge County, VA, Rockingham County, VA, Shenandoah County, VA, Warren County, VA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Mineral County, WV, Morgan County, WV, Pendleton County, WV, Pocahontas County, WV, Preston County, WV, Randolph County, WV, Tucker County, WV
The radar
The State College radar (KCCX), 95 km from the middle of the area, began a volume at 09:28 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
Pittsburgh, PA (KPIT), launched 00:00Z, 9.5 hours before the alert went out and 131 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
- 3184 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 202 m²/s²
- 0-3 km storm-relative helicity
- 191 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
328 ACUS11 KWNS 030929 SWOMCD SPC MCD 030928 PAZ000-NYZ000-MDZ000-VAZ000-WVZ000-031230- MESOSCALE DISCUSSION 0069 NWS STORM PREDICTION CENTER NORMAN OK 0328 AM CST TUE FEB 03 2004 AREAS AFFECTED...WRN PA...WV PNHDL...WRN/NRN VA...AND WRN/CNTRL MD CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION VALID 030928Z - 031230Z PRECIPITATION CHANGEOVER TO HEAVY SNOW...AT RATES IN EXCESS OF AN INCH PER HOUR...APPEARS LIKELY ACROSS WESTERN PENNSYLVANIA WITHIN NEXT COUPLE OF HOURS. MEANWHILE FREEZING RAIN AT RATES UP TO A TENTH OF AN INCH PER HOUR WILL CONTINUE/DEVELOP FROM NORTHWESTERN VIRGINIA INTO SOUTH CENTRAL PENNSYLVANIA. PRECIPITATION SHIELD IN ZONE OF ENHANCED ISENTROPIC ASCENT ALONG SOUTHERLY LOW-LEVEL JET AXIS CONTINUES TO SHIFT SLOWLY EASTWARD INTO THE UPPER OHIO VALLEY/CENTRAL APPALACHIANS REGION. BY 12Z... LOW-LEVEL JET AXIS APPEARS LIKELY TO EXTEND FROM NORTH CENTRAL NORTH CAROLINA THROUGH CENTRAL VIRGINIA AND WESTERN PENNSYLVANIA....WITH LOWER LEVELS WARMING ABOVE FREEZING TO SOUTHEAST OF CREST OF APPALACHIANS. SHALLOW LAYER OF SUBFREEZING SURFACE TEMPERATURES WILL PERSIST... HOWEVER...IN A NARROW CORRIDOR IN THE IMMEDIATE LEE OF THE APPALACHIANS. THIS WILL LIKELY RESULT IN PERIOD OF MODERATE FREEZING RAIN AND SIGNIFICANT ICING ROUGHLY ALONG AND WEST OF A LYNCHBURG/ CHARLOTTESVILLE/ FREDERICK LINE THROUGH MID MORNING. PRECIPITATION RATES WILL BE ENHANCED BY MID-LEVEL FORCING AHEAD OF SHORT WAVE TROUGH LIFTING OUT OF THE LOWER OHIO VALLEY...WHICH WILL BECOME FOCUSED FROM NORTHWESTERN VIRGINIA INTO WESTERN PENNSYLVANIA BY DAYBREAK...THEN CONTINUE TO SPREAD NORTHEASTWARD. MODELS ALL SUGGEST STRONG DEEP LAYER LIFT WILL CONTRIBUTE TO SUFFICIENT LOWER/MID TROPOSPHERIC COOLING FOR CHANGEOVER TO ALL SNOW ALONG/NORTH OF CREST OF APPALACHIANS ACROSS WESTERN PENNSYLVANIA BY/SHORTLY AFTER 12Z. CHANGEOVER MAY OCCUR EARLIER AROUND PITTSBURGH...BUT HEAVIEST SNOW FALL BY MID DAY APPEARS LIKELY IN SWATH SOUTHEAST OF PITTSBURGH INTO AREAS NEAR/SOUTH AND WEST OF BINGHAMTON NY. ..KERR.. 02/03/2004 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BGM...AKQ...BUF...CTP...LWX...RNK...PBZ...RLX... 40498024 41277986 41907855 42047779 42217668 41707628 41037626 40507707 39027749 37597851 37297969 38258019 39277976 39828008
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 2, 8:58 PM EST | Mesoscale Discussion | SPC | Allegany, Garrett | 5 hr |
| Feb 3, 11:45 AM EST | Mesoscale Discussion | SPC | Albany, Broome, Chemung, Chenango, Columbia, Cortland and 23 more | 6 hr |
Nearby
Mesoscale Discussions in Pennsylvania, 2004Mesoscale Discussions in Virginia, 2004Mesoscale Discussions in West Virginia, 2004Every mesoscale discussion in 2004
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.