Alert archive / Vermont / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 45, NWS Burlington, VT

July 17, 1998Orleans County, Vermont

NWS Burlington, VT issued this severe thunderstorm warning at Jul 17, 1998, 8:29 PM EDT for Orleans County, Vermont. It was in force for 51 min. 2 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
Jul 17, 1998, 8:29 PM EDT (00:29 UTC)
Expired
Jul 17, 1998, 9:20 PM EDT
In force
51 min
Issued by
NWS Burlington, VT
Area
Whole counties

County Orleans County, VT

The radar

The Burlington radar (KCXX), 81 km from the middle of the area, began a volume at 00:30 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

TimeReportWhereRemark
Jul 17, 8:30 PM EDTHail 1.75North Troy, VT
Jul 17, 8:35 PM EDTThunderstorm WindNewport, VT

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

Albany, NY (KALY), launched 00:00Z, 0.5 hours before the alert went out and 270 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, Albany, NY at 00:00Z on 1998-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 598 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, Albany, NY at 00:00Z on 1998-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -31 square meters per square second.193958Sfc1 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
598 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
1135 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
-31 m²/s²
0-3 km storm-relative helicity
-2 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.5

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 Burlington, VT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 17, 2:10 PM EDT, 6 hours 19 minutes earlier.

Area forecast discussion, Jul 17, 2:10 PM EDT, 6 hours 19 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
210 PM EDT FRI JUL 17 1998

COORD WITH ALB.  MAIN WX PROBLEM WL CONTINUE TO BE THREAT OF HVY
RAIN IN TSRA THRU FIRST PART OF TONITE.

CURRENTLY: KCXX/KTYX NOT SHOWING MUCH IN WAY OF PCPN ACRSS FA
ATTM...JUST ISOLD SHRA NRN PTN CHMPLN VLY.  THIS ACTIVITY ASSOCD
WITH PREFRONTAL TROF WHICH EXTENDS SW INTO CNTRL PA.  XPC THIS
ACTIVITY TO INCR DURING MID-LATE PM.  A MORE SGFNT LINE OF SHRA/TSRA
INDICATED ON RADAR AND STLT PICS OVR ERN GRTLKS...IN ASSOCIATION
WITH CDFNT.  THIS ACTIVITY ALSO ON INCR AS IT ENTERS MOIST UNSTABLE
AIRMASS. (PW'S ACRS FA NEAR 1.5", SFC DWPTS ARND 70...CAPES 500-1000
J/KG & LI'S -2 TO -5).  MAIN THREAT WITH TSRA IS POTENTIAL FOR HVY
RAIN.

12Z GUIDANCE SHOWS NO MAJOR SURPRISES.  LLVL WNDSHFT PROGGED TO
OCCUR THIS EVENING...WHILE MID LVL SHRTWV NOT EXPECTED TO CLR FA TIL
LATE TON/EARLY SAT.  AS LLVL FLOW BCMS W-NW THIS EVEN...THREAT OF
HEAVIEST RAIN WL BE OVR UPSLOPE FAVORED AREAS OF ADRNDKS & GREEN
MTNS.  ALTHO THREAT OF HVY PCPN WL DIMINISH LATER THIS EVEN...WITH
LAGGING SHRTWV THE CHC OF SHRA WL CONTINUE OVRNGT...ESPEC IN NRN VT.

NOTICEABLY DRIER AIR MOVES INTO FA SAT.  BKN SC AT TIMES DURING AM
WL YIELD TO PLENTY OF SS AS COOL POOL ALOFT LIFTS NEWRD AND CNTR OF
HI PRES BLDS EAST FROM GRTLKS.

HI PRES SLIDES OFF MID ATLC CST SAT NITE/SUN.  RETURN SOUTHERLY FLOW
DVLPS...AND WARMUP BEGINS ONCE AGAIN.  XPC SOME MID/HI CLDS...BUT
M/S SHOULD COVER IT.

FWC/FAN TEMPS VERY CLOSE...AND GUIDANCE ACCEPTED.

RJS

Nearby

Severe Thunderstorm Warnings in Vermont, 1998Every severe thunderstorm warning in 1998

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.