Alert archive / Maryland / Flash Flood Warnings in 2000

Flash Flood Warning 7, NWS Baltimore/Washington

June 26, 2000Montgomery County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Jun 26, 2000, 5:40 PM EDT for Montgomery County, Maryland. It was in force for 65 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 26, 2000, 5:40 PM EDT (21:40 UTC)
Expired
Jun 26, 2000, 6:45 PM EDT
In force
65 min
Issued by
NWS Baltimore/Washington
Area
Whole counties

County Montgomery County, MD

The radar

The Sterling radar (KLWX), 30 km from the middle of the area, began a volume at 21:39 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.7 hours before the alert went out and 27 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.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2000-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 130 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2000-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
130 J/kg
Mixed-layer CIN
-170 J/kg
Mixed-layer LCL
979 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS51 KLWX 262141
FFWLWX
MDC031-262245-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BALTIMORE-WASHINGTON
540 PM EDT MON JUN 26 2000

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  MONTGOMERY COUNTY IN CENTRAL MARYLAND

* UNTIL 645 PM EDT

* AT 540 PM EDT...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY
  RAIN 7 MILES SOUTHWEST OF POOLESVILLE...MOVING NORTHEAST AT 25 MPH.

* THE THUNDERSTORM WITH EXCESSIVE RAINFALL WILL BE NEAR...
   POOLESVILLE AT 548 PM EDT
   BOYDS AT 602 PM EDT
   GERMANTOWN AT 606 PM EDT
   GAITHERSBURG AT 608 PM EDT

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. 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.

TO REPORT SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN STERLING VIRGINIA.

JA/DMW

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 26, 2:30 PM EDT, 3 hours 10 minutes earlier.

Area forecast discussion, Jun 26, 2:30 PM EDT, 3 hours 10 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
230 PM EDT MON JUN 26 2000

MDL GUIDANCE LATE THIS AFTRN AND USING ICWF...SO FCST BASED ON 00Z
CYCLE WITH LAST MINUTE INPUT FROM WHAT IS AVBL FROM THE 12Z CYCLE.

ATMS OVR THE AREA CONTS UNSTABLE THIS AFT. NO SYNOPTIC SCALE TRIGGER
TO ACT ON. HOWEVER...ISOLD/SCT CNVCTN PSBL THRU EARLY EVE ALONG
MESOSCALE FEATURES AND OVR MTNS WHERE OROGRAPHIC LIFT WL ENHANCE
DVLPMT. AFTER SUNSET...EXPECT ACTIVITY TO DIE OFF AND BE GONE BY
MIDNGT.

LOOKS LIKE A BETTER CHC OF MORE ORGANIZED CONVECTION ON TUE. SHRTWV
MVS TOWARD THE AREA FM W. THE ASSOCD SFC BNDRY APPROACHES DURING THE
AFT/EVE HRS. WILL CONTINUE WITH THE IDEA OF LIKELY POPS. WL WORD IT
AS AFT/EVE OVR THE MTNS AND LATE AFT/EVE E OF THE MTNS. SFC BNDRY
GETS HUNG UP OVR THE AREA TUE NIGHT AND WED AS IT BECOMES PARALLEL
TO UPR LVL FLO SO WL KEEP POPS IN FCST INTO 4TH PD.

FCSTID = 15

.LW!X...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 25, 8:52 PM EDTSevere Thunderstorm WarningLWXMontgomery38 min
Jun 25, 9:02 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick58 min
Jun 25, 9:48 PM EDTSevere Thunderstorm WarningLWXBaltimore42 min
Jun 25, 11:48 PM EDTFlash Flood WarningLWXMontgomery117 min
Jun 26, 12:56 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Howard, Prince George's64 min
Jun 26, 1:11 AM EDTSevere Thunderstorm WarningLWXBaltimore, City of Baltimore49 min
Jun 26, 3:52 PM EDTSevere Thunderstorm WarningLWXHoward, Montgomery38 min
Jun 26, 4:24 PM EDTSevere Thunderstorm WarningLWXBaltimore, Harford51 min
Jun 26, 4:30 PM EDTSevere Thunderstorm WarningLWXCharles45 min
Jun 26, 4:46 PM EDTFlash Flood WarningLWXHoward, Montgomery59 min
Jun 26, 6:17 PM EDTSevere Thunderstorm WarningLWXCalvert, Saint Mary's43 min

Nearby

Flash Flood Warnings in Maryland, 2000Every flash flood warning in 2000

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.