Alert archive / Virginia / Mesoscale Discussions in 2010
Mesoscale Discussion 2021
The Storm Prediction Center issued this mesoscale discussion at Oct 27, 2010, 3:21 PM EDT for 4 states. It was in force for 54 min.
The area
The outline as issued.
The facts
- Issued
- Oct 27, 2010, 3:21 PM EDT (19:21 UTC)
- Expired
- Oct 27, 2010, 4:15 PM EDT
- In force
- 54 min
- Issued by
- the Storm Prediction Center
All 60 counties
Kent County, DE, Sussex County, DE, Calvert County, MD, Caroline County, MD, Charles County, MD, Dorchester County, MD, Queen Anne's County, MD, Saint Mary's County, MD, Somerset County, MD, Talbot County, MD, Wicomico County, MD, Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ, Accomack County, VA, Amelia County, VA, Brunswick County, VA, Buckingham County, VA, Caroline County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Fredericksburg, VA, City of Hopewell, VA, City of Petersburg, VA, City of Richmond, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Gloucester County, VA, Goochland County, VA, Greensville County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, James City County, VA, King and Queen County, VA, King George County, VA, King William County, VA, Lancaster County, VA, Louisa County, VA, Lunenburg County, VA, Mathews County, VA, Mecklenburg County, VA, Middlesex County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Richmond County, VA, Spotsylvania County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA
The radar
The Sterling radar (KLWX), 104 km from the middle of the area, began a volume at 19:23 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.4 hours before the alert went out and 97 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
- 402 J/kg
- Mixed-layer CIN
- -32 J/kg
- Mixed-layer LCL
- 591 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 226 m²/s²
- 0-3 km storm-relative helicity
- 239 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 4.8
The text
As transmitted, in the capitals the NWS used until 2016.
488
ACUS11 KWNS 271922
SWOMCD
SPC MCD 271921
NJZ000-DEZ000-MDZ000-VAZ000-NCZ000-272015-
MESOSCALE DISCUSSION 2021
NWS STORM PREDICTION CENTER NORMAN OK
0221 PM CDT WED OCT 27 2010
AREAS AFFECTED...SOUTHERN/EASTERN VA AND EASTERN MD TO DE/SOUTHERN
NJ
CONCERNING...TORNADO WATCH 733...
VALID 271921Z - 272015Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 733 CONTINUES.
TORNADO WATCH 733 CONTINUES UNTIL 00Z...WITH CONTINUING POTENTIAL
FOR ISOLATED TORNADOES AND DAMAGING WINDS.
A COUPLE OF FAST MOVING MARGINAL SUPERCELLS/SMALL LINEAR SEGMENTS
CONTINUE TO STEADILY PROGRESS EAST-NORTHEASTWARD ACROSS THE EASTERN
MD SHORE/DE VICINITY AT MID AFTERNOON. WITH THIS ACTIVITY OCCURRING
IN WHAT IS NOW A MODERATELY UNSTABLE AIRMASS...RATHER STRONG WIND
FIELDS...WITH 50+ KT AT 2-3 KM AND ABOVE PER THE DOVER AFB WSR-88D
VWP...WILL SUPPORT AT LEAST SOME SHORT TERM POTENTIAL FOR WIND
DAMAGE/BRIEF TORNADO PRIOR TO STORMS CLEARING THE COAST.
OTHERWISE...LATEST THINKING IS THAT STORMS SHOULD FURTHER INCREASE
THE REMAINDER OF THE AFTERNOON FROM THE NORTHERN NC PIEDMONT INTO
SOUTH-CENTRAL/SOUTHEAST VA. SURFACE TEMPERATURES HAVE NOW WARMED
INTO THE LOWER/MIDDLE 80S F...WHICH IS CONTRIBUTING TO AS MUCH AS
1000-1250 J/KG OF MLCAPE ON THE IMMEDIATE WARM SIDE OF THE
SOUTHWEST-NORTHEAST ORIENTED FRONTAL ZONE. GIVEN THE MAGNITUDE OF
DEEP LAYER/LOW LEVEL SHEAR ACROSS THE REGION PER REGIONAL WSR-88D
VWP DATA...ANY SUSTAINED /ESPECIALLY CG LIGHTNING-YIELDING/ UPDRAFTS
SHOULD EASILY ATTAIN ROTATION AND/OR DEVELOP INTO SMALL BOWING
SEGMENTS CAPABLE OF DAMAGING WINDS/FEW TORNADOES.
..GUYER.. 10/27/2010
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...AKQ...LWX...RAH...RNK...
LAT...LON 39077630 39737487 39497429 37357606 36447803 36767927
37567855 38657716 39077630SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 27, 5:28 AM EDT | Mesoscale Discussion | SPC | Sussex | 2 hr |
| Oct 27, 11:54 AM EDT | Mesoscale Discussion | SPC | Kent, New Castle | 66 min |
| Oct 27, 12:13 PM EDT | Tornado Watch | SPC | Kent, New Castle, Sussex | 8 hr |
| Oct 27, 4:48 PM EDT | Mesoscale Discussion | SPC | Kent, Sussex | 57 min |
| Oct 26, 11:05 PM EDT | Mesoscale Discussion | SPC | Allegany, Baltimore, Carroll, Frederick, Howard, Montgomery and 1 more | 55 min |
| Oct 27, 12:24 AM EDT | Mesoscale Discussion | SPC | Allegany, Baltimore, Carroll, Frederick, Howard, Montgomery and 1 more | 66 min |
| Oct 27, 7:16 PM EDT | Mesoscale Discussion | SPC | Calvert, Charles, Dorchester, Saint Mary's, Somerset, Wicomico and 1 more | 59 min |
| Oct 27, 7:46 PM EDT | Tornado Watch | SPC | Calvert, Charles, Dorchester, Saint Mary's, Somerset, Wicomico and 1 more | 8 hr |
| Oct 27, 2:44 AM EDT | Tornado Watch | SPC | Amelia, Appomattox, Brunswick, Buckingham, Campbell, Charles City and 34 more | 7 hr |
| Oct 27, 4:03 PM EDT | Mesoscale Discussion | SPC | Mecklenburg | 87 min |
Nearby
Mesoscale Discussions in Virginia, 2010Mesoscale Discussions in Maryland, 2010Mesoscale Discussions in New Jersey, 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.