Alert archive / Virginia / Flash Flood Warnings in 2001
Flash Flood Warning 21, NWS Baltimore/Washington
NWS Baltimore/Washington issued this flash flood warning at Jun 22, 2001, 5:34 PM EDT for Loudoun County, Virginia; Montgomery County, Maryland. It was in force for 116 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Jun 22, 2001, 5:34 PM EDT (21:34 UTC)
- Expired
- Jun 22, 2001, 7:30 PM EDT
- In force
- 116 min
- Issued by
- NWS Baltimore/Washington
- Area
- Whole counties
Counties Montgomery County, MD, Loudoun County, VA
The radar
The Sterling radar (KLWX), 16 km from the middle of the area, began a volume at 21:34 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, 9.6 hours before the alert went out and 18 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
- 933 J/kg
- Mixed-layer CIN
- -78 J/kg
- Mixed-layer LCL
- 704 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 108 m²/s²
- 0-3 km storm-relative helicity
- 103 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.3
The text
As transmitted, in the capitals the NWS used until 2016.
000 WGUS51 KLWX 222138 CCA FFWLWX MDC031-VAC107-222330- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE BALTIMORE-WASHINGTON 534 PM EDT FRI JUN 22 2001 THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A * FLASH FLOOD WARNING FOR... MONTGOMERY COUNTY IN CENTRAL MARYLAND LOUDOUN COUNTY IN NORTHERN VIRGINIA * UNTIL 730 PM EDT * AT 529 PM EDT...WEATHER SERVICE DOPPLER RADAR INDICATED A THUNDERSTORM WITH VERY HEAVY RAINFALL OVER PURCELLVILLE...MOVING NORTHEAST AT 25 MPH. IF WATER IS FLOWING ACROSS A ROADWAY TURN YOUR VEHICLE AROUND AND FIND AN ALTERNATE ROUTE. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHER GROUND. A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY. RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK HIGHER GROUND.l
What forecasters said that day
The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Baltimore/Washington wrote its last area forecast discussion before this flash flood warning went out at Jun 22, 3:40 PM EDT, 1 hour 54 minutes earlier.
Area forecast discussion, Jun 22, 3:40 PM EDT, 1 hour 54 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 340 PM EDT FRI JUN 22 2001 AT 18Z...SEVERAL TSTMS MAINLY BLUE RIDGE W PRODUCING VERY HEAVY RAINFALL...HAIL...AND POSSIBLY STRONG WINDS. STORMS SEEM TO REDEVELOP OVER SAME AREAS WHICH ADDS TO FLOODING THREAT. TSTMS AND SHRA WILL CONTINUE THROUGH NIGHT DUE TO APPROACHING FRONTAL BDRY...STRONG UL DIVERGENCE...PLENTY OF VVEL AT 700 AND 500MB IN ADDITION TO 850MB LOW MOVING OVHD. WILL HAVE 80 POPS CWA WIDE. WILL ALSO CONTINUE FLASH FLOOD WATCH UNTIL 4 AM FOR BLUE RIDGE W AND CHO AREA. EXPECT HAIL/WIND THREAT TO DIMINISH A FEW HOURS AFT SUNSET DUE TO LOSS OF DAYTIME HEATING BUT HVY RAIN WILL PROBABLY CONTINUE TO BE A PROBLEM BECAUSE PRECIP H20 VALUES REMAIN AROUND 1.75 IN. MOST CWA UNDER SVR TSTM WATCH THRU 7PM. FRONT REACHES NW CWA BY MIDDAY BUT DOESNT REACH FAR SE CWA UNTIL SUN MORNING. RELATIVELY DRIER AIR WILL COME IN BEHIND FRONT AND SHUD GIVE US A RAIN FREE PERIOD FROM W TO E SUN MORN THRU MON AFT. UL LOW CUTS OFF OVER SE US AND RETROGRADES A BIT MON INTO TUE. THIS TURNS WINDS E FOR A TIME MON AND BRINGS IN SOME RH OFF THE WATER AND ALSO SPINS SOME WEAK IMPULSES FROM S TO N THRU CWA. THIS WILL GIVE ATMOS SOME RH AND LIFT TO WORK WITH...ESPECIALLY MON AFT...TO CREATE WIDELY SCT SHRA/-TSRA. ATMOS WONT CHANGE SIG TUE SO WILL KEEP 30 POP FOR AFT CONVECTION IN FCST. HI PRES OVER THE OCEAN STARTS TO INFLUENCE MID ATLANTIC WEATHER WED THRU FRI SO WILL FCST DRY COND. REGARDING TEMPS...THOUGHT FWC LOW TEMPS WERE TOO COLD NEXT FEW NIGHT DUE TO ELEVATED DEW PTS. STAYED NEAR GUIDANCE REST OF FCST. FCSTID = 36 DCA 70 80 65 82 / 80 70 50 30 BWI 70 80 65 82 / 80 70 50 30 MRB 68 77 64 83 / 80 60 40 20 IAD 69 79 62 82 / 80 70 50 30 CHO 69 79 65 81 / 80 70 50 30 HGR 66 75 63 80 / 80 60 40 20 NHK 71 80 68 81 / 80 70 50 30 .LWX... DC...NONE. MD...FLASH FLOOD WATCH THRU 400 AM FOR ZONES MDZ002>003. VA...FLASH FLOOD WATCH THRU 400 AM FOR ZONES VAZ021...VAZ025>031... VAZ036>040...VAZ050>051. WV...FLASH FLOOD WATCH THRU 400 AM FOR ZONES WVZ048>055. MMARGRAF
In the hours before
Local storm report, Jun 22, 4:31 PM EDT, 1 hour 3 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
431 PM EDT FRI JUN 22 2001
TIME(EDT) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0215 PM 6 NW WINCHESTER VA .75 INCH HAIL
06/22/01 FREDERICK REPORTED BY SKYWARN
0350 PM COUNTYWIDE VA FLASH FLOODS
06/22/01 FREDERICK BACK CREEK OVERFLOWING
BANKS. BOY SCOUT CAMP
EVACUATED. REPORTED BY
SKYWARN.
0400 PM COUNTYWIDE VA FLASH FLOODS
06/22/01 FREDERICK ROUTE 50 EAST...ROUTE
605...ROUTE 614 AND ROUTE
50 FLOODED. REPORTED BY
SKYWARN AND MEDIA.
0425 PM FREDERICK MD .88 INCH HAIL
06/22/01 FREDERICK
MKMThe office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 21, 8:10 PM EDT | Severe Thunderstorm Warning | LWX | Shenandoah | 65 min |
| Jun 22, 12:15 AM EDT | Flash Flood Warning | LWX | Orange | 2 hr |
| Jun 22, 1:23 PM EDT | Flash Flood Warning | LWX | Frederick | 3 hr |
| Jun 22, 1:39 PM EDT | Severe Thunderstorm Warning | LWX | Warren | 51 min |
| Jun 22, 2:00 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, City of Winchester | 45 min |
| Jun 22, 4:08 PM EDT | Tornado Warning | LWX | Clarke, Warren | 37 min |
| Jun 22, 4:13 PM EDT | Flash Flood Warning | LWX | Frederick, City of Winchester | 3 hr |
| Jun 22, 4:20 PM EDT | Severe Thunderstorm Warning | LWX | Culpeper, Fauquier, Rappahannock | 55 min |
| Jun 22, 4:23 PM EDT | Flash Flood Warning | LWX | Shenandoah, Warren | 3 hr |
| Jun 22, 4:40 PM EDT | Flash Flood Warning | LWX | Nelson | 3 hr |
| Jun 22, 6:03 PM EDT | Severe Thunderstorm Warning | LWX | Loudoun | 57 min |
| Jun 22, 6:09 PM EDT | Flash Flood Warning | LWX | Rockingham | 3 hr |
| Jun 22, 7:22 PM EDT | Flash Flood Warning | LWX | Shenandoah | 3 hr |
| Jun 22, 7:24 PM EDT | Flash Flood Warning | LWX | Loudoun | 3 hr |
| Jun 22, 7:31 PM EDT | Severe Thunderstorm Warning | LWX | Prince William, City of Manassas, City of Manassas Park | 59 min |
| Jun 22, 7:31 PM EDT | Severe Thunderstorm Warning | LWX | Fauquier | 59 min |
| Jun 22, 3:56 PM EDT | Severe Thunderstorm Warning | LWX | Frederick | 49 min |
| Jun 22, 4:30 PM EDT | Flash Flood Warning | LWX | Allegany | 3 hr |
| Jun 22, 4:34 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 41 min |
| Jun 22, 4:43 PM EDT | Severe Thunderstorm Warning | LWX | Frederick | 47 min |
| Jun 22, 6:58 PM EDT | Flash Flood Warning | LWX | Carroll | 3 hr |
Nearby
Flash Flood Warnings in Virginia, 2001Flash Flood Warnings in Maryland, 2001Every flash flood warning in 2001
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.