Alert archive / Maryland / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 128, NWS Baltimore/Washington

August 27, 2001Saint Mary's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Aug 27, 2001, 5:14 PM EDT for Saint Mary's County, Maryland. It was in force for 31 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Aug 27, 2001, 5:14 PM EDT (21:14 UTC)
Expired: Aug 27, 2001, 5:45 PM EDT
In force: 31 min
Issued by: NWS Baltimore/Washington
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Saint Mary's County, MD

What was reported inside it

Time	Report	Where	Remark
Aug 27, 5:30 PM EDT	Thunderstorm Wind	Point Lookout, MD	Trees were downed in Point Lookout State Park.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 9.2 hours before the alert went out and 104 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 17 J/kg
Mixed-layer CIN: -171 J/kg
Mixed-layer LCL: 1037 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: -15 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Aug 27, 3:15 PM EDT, 1 hour 59 minutes earlier.

Area forecast discussion, Aug 27, 3:15 PM EDT, 1 hour 59 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
315 PM EDT MON AUG 27 2001

AT 19Z...SCT SHRA/TSRA DEVELOPING ALONG AND AHEAD OF BDRY CREATED BY
DIFF HEATING FROM FREDERICK MD TO STAUNTON VA. SFC FRONT ASSOC WITH
700MB TROF HARD TO FIND IN HIGH TERRAIN BUT WINDS HAVE TURNED NW AND
DEW PTS ARE DROPPING IN FAR NW CWA. EXPECT FRONT TO PUSH SE AND EXIT
FAR SE BEFORE 06Z ENDING PRECIP FROM NW TO SE. WILL CARRY 20 POP W
OF BLUE RIDGE EARLY TO COVER LEFTOVER PRECIP NEXT FEW HRS AND GO
WITH A 30 POP E OF BLUE RIDGE...WITH THE EXCEPTION OF A 40 POP IN
FAR SE. BEST CHANCE OF -TSRA SE OF A LINE FROM DCA TO JUST E OF CHO
WHERE SUNSHINE PREVAILED TODAY AND TEMPS HAVE REACHED UPPER 80S AND
DEW PTS HAVE CLIMBED INTO THE LOW 70S.

WINDS TURN WNW BEHIND FRONT OVERNIGHT WHICH CREATES DOWNSLOPE 850MB
FLOW. THIS HELPS TO SCOUR OUT MOISTURE E OF RIDGES TUE AHEAD OF NEXT
FRONT WHICH IS FCST TO CROSS CWA BETWEEN 00Z AND 06Z TUE NIGHT.
THIS WILL CAUSE FRONT TO BE MOISTURE STARVED AS IT PASSES THROUGH.
OTHER CONS TO PRECIP...MOST DYNAMICS PASS WELL N OF CWA AND BDRY
WILL BE COMING THROUGH MOST OF CWA AFTER SUNSET. DUE TO SPILLOVER
MOISTURE AND TIMING OF FRONT WILL KEEP 30 POP OF AFT/EARLY EVE
SHRA/TSRA FROM BLUE RIDGE W WHERE CONVECTION CANNOT BE ENTIRELY
RULED OUT. HAVE DECIDED TO REMOVE POPS FROM REST OF CWA TUE.

FRONT WASHES OUT JUST SE OF AREA WED AND DRIER AIR FILTERS IN FROM
THE N AS HI PRES BUILDS IN. THE HI PUSHES OFFSHORE THU AND OUR WINDS
TURN S. AVN/CANADIAN/MRF ALL SHOW A BATCH OF MOISTURE DRAWN UP FROM
THE GULF WED AND DEVELOP A SFC LOW OVER THE MID MISS VALLEY THU.
THIS FEATURE APPROACHES CWA THU NITE INTO FRI AHEAD OF A COLD FRONT
MOVING SE FROM THE GREAT LAKES REGION. LL RH INCREASES RAPIDLY OVER
CWA THU AND THU NITE WITH GOOD WAA. BY FRI ATMOS IS UNSTABLE ENOUGH
TO SUPPORT AFT SHRA/TSRA. COLD FRONT PASSES THRU CWA SAT SO
CHANCE POPS WARRENTED AGAIN. STRONG CAA FCST BY MRF SAT NIGHT AS HI
PRES PUSHES INTO REGION. HI WILL BE OVER CWA BY MON.

REGARDING TEMPS...DID NOT STRAY FAR FROM GUIDANCE THRU FCST. COOL
DOWN FOR LABOR DAY WEEKEND ON MAV LOOKS REASONABLE BASED ON STRENGTH
AND ORIGIN OF SFC HI.

FCSTID = 36
DCA   69  88  68  85 /  30  20  20   0
BWI   65  88  65  84 /  30  20  20   0
MRB   63  88  63  84 /  20  30  30   0
IAD   64  88  64  84 /  30  20  20   0
CHO   65  88  64  84 /  40  10  10  10
HGR   60  85  60  82 /  20  30  30   0
NHK   70  87  68  83 /  40  10  10  10
W99   61  85  61  82 /  20  30  30   0

.LWX...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.

MMARGRAF

Nearby

Severe Thunderstorm Warnings in Maryland, 2001 Every severe thunderstorm 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.