Alert archive / Maryland / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 15, NWS Baltimore/Washington
NWS Baltimore/Washington issued this severe thunderstorm warning at May 2, 2002, 3:25 PM EDT for Montgomery County, Maryland. It was in force for 50 min. 7 reports 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
- May 2, 2002, 3:25 PM EDT (19:25 UTC)
- Expired
- May 2, 2002, 4:15 PM EDT
- In force
- 50 min
- Issued by
- NWS Baltimore/Washington
- Area
- Counties, with a storm outline in the text
County Montgomery County, MD
The radar
The Sterling radar (KLWX), 30 km from the middle of the area, began a volume at 19:27 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 2, 3:29 PM EDT | Hail 1.75 | Darnestown, MD | Golfball sized hail was reported. |
| May 2, 3:30 PM EDT | Thunderstorm Wind | Gaithersburg, MD | A large oak tree was downed onto a business and trees and power lines were downed onto Route 28. |
| May 2, 3:30 PM EDT | Hail 1.75 | Gaithersburg, MD | Dime to golfball sized hail was reported. |
| May 2, 3:35 PM EDT | Hail 0.8 | Rockville, MD | Dime sized hail fell. |
| May 2, 3:38 PM EDT | Hail 1.75 | Derwood, MD | Hail up to golf ball size fell. |
| May 2, 3:40 PM EDT | Hail 1.5 | Olney, MD | Walnut sized hail was reported. |
| May 2, 3:50 PM EDT | Hail 1.75 | Brookeville, MD | Golfball sized hail fell. |
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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 2, 2:30 PM EDT | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Wallops Is Stn, VA (KWAL), launched 12:00Z, 7.4 hours before the alert went out and 206 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
- 12 J/kg
- Mixed-layer CIN
- -90 J/kg
- Mixed-layer LCL
- 540 m above ground
- 0-6 km bulk shear
- 82 kt
- 0-1 km storm-relative helicity
- 408 m²/s²
- 0-3 km storm-relative helicity
- 464 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.0
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 May 2, 2:55 PM EDT, 30 minutes earlier.
Area forecast discussion, May 2, 2:55 PM EDT, 30 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 255 PM EDT THU MAY 2 2002 TOR WATCH IN EFFECT FOR ENTR FA UNTIL 9PM (01Z). AN AREA OF SHRAS/TSRAS HAD MOVED INTO FA FM WV THIS AFTN. WL BE WATCHING SVR AND FLSH FLOOD THREAT. SHRAS/TSRAS WL BE LIKELY INTO THIS EVE AS CDFNT EXPECTED TO BE RIGHT OVR THE FA AT 00Z. AMS DRIES OUT AFT 06Z BHND FRONT. WL BCM BREEZY DUE TO GRADIENT BETW DEEPENING LOW PRES N OF THE AREA AND HIGH PRES ADVANCING EWD AND CAA. HIGH PRES AND DRY AMS WL MOV ACRS RGN FRI AND FRI NGT. CDFNT WL BCM STNRY OVR CAROLINAS. SOME CI WL MOV INTO THE AREA LATE FRI NIGHT AS NXT S/W APPCHS FM MIDWEST. LOW PRES ASSOCD W/THE S/W WL MOV E ALG STNRY BDRY S OF FA. MOISTURE WL SPREAD N THRUT THE AREA ON SAT AS LOW MOVES E THRU CAROLINAS. IN ADDITION...HIGH PRES WL MOV OFFSHORE AND PUMP ATLC MOISTURE INTO RGN. WL ADD CHC OF RA TO AREA SAT AFTN. FWC TEMPS AND 06Z MAV TEMPS WERE SIMILIAR AND SEEMED RSNBL. ZONAL FLOW WL PREVAIL OVR RGN SAT NGT THRU SUN NGT. ANOTHER S/W WL MOV THRU THE AREA MON AND MON NGT BRINGING CHC OF RA. UPR RDG FCST TO BLD INTO RGN DAY/S 5 THRU 7. .LWX... DC...FLOOD WATCH FOR THIS AFTERNOON FOR ZONE DCZ001. MD...FLOOD WATCH FOR THIS AFTERNOON FOR ZONES MDZ002>007...MDZ009>011...MDZ013>014...MDZ016>018. VA...FLOOD WATCH FOR THIS AFTERNOON FOR ZONES VAZ021...VAZ025>031...VAZ036>042...VAZ050>057. WV...FLOOD WATCH FOR THIS AFTERNOON FOR ZONES WVZ048>055. ARTHUR
The office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 2, 7:40 AM EDT | Special Marine Warning | LWX | 50 min | |
| May 2, 7:40 AM EDT | Special Marine Warning | LWX | 50 min | |
| May 2, 8:26 AM EDT | Special Marine Warning | LWX | 49 min | |
| May 2, 2:24 PM EDT | Severe Thunderstorm Warning | LWX | Albemarle, Nelson | 36 min |
| May 2, 3:08 PM EDT | Special Marine Warning | LWX | 97 min | |
| May 2, 3:10 PM EDT | Severe Thunderstorm Warning | LWX | Fairfax, Loudoun | 35 min |
| May 2, 3:49 PM EDT | Severe Thunderstorm Warning | LWX | King George, Spotsylvania, Stafford, City of Fredericksburg | 26 min |
| May 2, 4:07 PM EDT | Special Marine Warning | LWX | 83 min | |
| May 2, 4:07 PM EDT | Special Marine Warning | LWX | 83 min | |
| May 2, 4:07 PM EDT | Special Marine Warning | LWX | 83 min | |
| May 2, 3:44 PM EDT | Severe Thunderstorm Warning | LWX | Howard | 46 min |
| May 2, 4:05 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, City of Baltimore | 40 min |
| May 2, 4:22 PM EDT | Severe Thunderstorm Warning | LWX | Harford | 38 min |
| May 2, 5:15 PM EDT | Tornado Warning | LWX | Harford | 30 min |
Nearby
Severe Thunderstorm Warnings in Maryland, 2002Every severe thunderstorm warning in 2002
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; radar from the NEXRAD Level II archive.