Alert archive / California / Flash Flood Warnings in 1998

Flash Flood Warning 14, NWS Medford, OR

July 22, 1998Siskiyou County, California

NWS Medford, OR issued this flash flood warning at Jul 22, 1998, 6:15 PM PDT for Siskiyou County, California. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 22, 1998, 6:15 PM PDT (01:15 UTC)
Expired: Jul 22, 1998, 10:00 PM PDT
In force: 4 hr
Issued by: NWS Medford, OR
Area: Whole counties

County Siskiyou County, CA

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 00:00Z, 1.3 hours before the alert went out and 89 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: 1074 J/kg
Mixed-layer CIN: -122 J/kg
Mixed-layer LCL: 2426 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: -12 m²/s²
0-3 km storm-relative helicity: 65 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 
TTAA00 KMFR 230121
FFWMFR
CAC093-230510-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MEDFORD OR
615 PM PDT WED JUL 22 1998

THE NATIONAL WEATHER SERVICE IN MEDFORD HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL SISKIYOU COUNTY IN NORTH CENTRAL CALIFORNIA

* UNTIL 1000 PM PDT

* AT 605 PM... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAIN OVER THE MARBLE MOUNTAINS OF
  CENTRAL SISKIYOU COUNTY. THE STORMS WERE NEARLY STATIONARY.

* VERY HEAVY RAIN HAS BEEN FALLING OVER THE MARBLE MOUNTAINS INTO
  THE TRIBUTARIES OF THE SCOTT RIVER.  RAPID RISES AND FLOODING ARE
  LIKELY IN SOME SMALL STREAMS ON THE WEST SIDE OF THE SCOTT VALLEY.

  RAPID RISES ARE POSSIBLE ON THE SCOTT RIVER ESPECIALLY ON THE EAST
  FORK AND BELOW FORT JONES.

  THIS FLASH FLOOD WARNING EXPANDS THE PREVIOUS FLASH FLOOD WARNING
  ISSUED AT 410 PM.

  DON'T DRIVE ACROSS FLOODED ROADS! MOST FLASH FLOOD DEATHS OCCUR IN
  AUTOMOBILES.

AF

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 Medford, OR wrote its last area forecast discussion before this flash flood warning went out at Jul 22, 2:30 PM PDT, 3 hours 45 minutes earlier.

Area forecast discussion, Jul 22, 2:30 PM PDT, 3 hours 45 minutes before

SOUTHWEST OREGON/NORTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
230 PM PDT WED JUL 22 1998

INTRUSTION OF MONSOONAL MOISTURE WILL INCREASE THREAT OF TSTMS OVER
THE NEXT FEW DAYS.  INCREASINGLY SSE FLOW BETWEEN THE GREAT BASIN
HIGH AND WEAK TROUGH PATTERN ALONG THE WEST COAST WILL BRING
SCATTERED TSTMS TO SC ORE/NERN CA AND POSSIBLY INTO THE ROGUE BASIN.
AMPLE LOW LEVEL MOISTURE IN PLACE WITH DEW POINTS THIS AFTN ARND 60
DEG C FROM SHASTA VALLEY NWD INTO ROGUE AND KLAMATH BASINS.
CONVECTION BEGINNING AT TO FIRE AT 21Z ON LEADING EDGE OF DEBRIS
CLOUDS AND HEAD OF MOISTURE PLUME MVG INTO NRN CA/NWRN NV. CONCERNS
WILL SHIFT TO FLASH FLOOD POTENTIAL OVER NEXT COUPLE OF DAYS DUE TO
MOISTENING AIRMASS AND LIGHT STEERING CURRENTS.  COAST WILL REMAIN
UNDER INFLUENCE OF MARINE LAYER. JUST MINOR COOLING WITH INCREASE IN
CLOUDS AND TSTM ACTIVITY. NO MAJOR CHANGES INTO THE WEEKEND AS LARGE
SCALE PATTERN CHANGES LITTLE.   FOSTER

KMFR...NONE

.KMAX...VCP 21

...SEE PDXCCFPDX FOR CODED CITIES FORECAST

MFR UU 066/098 066/097 066 101222
LMT BB 060/093 059/093 058 103443
RBG UU 061/091 061/091 061 101111
4BK BB 055/066 055/064 055 100000
OTH BB 056/065 056/065 056 100000
YKA UU 061/098 060/098 059 102443
MHS BB 059/089 059/089 058 103443
S11 BB 056/093 057/093 056 103443

The office that day

Everything else NWS Medford, OR issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 22, 5:35 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	50 min
Jul 22, 6:42 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	48 min

Nearby

Flash Flood Warnings in California, 1998 Every flash flood 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; the sounding from the Mesonet's radiosonde archive.