Alert archive / Alaska / Flash Flood Warnings in 2004

Flash Flood Warning 4, NWS Fairbanks, AK

July 20, 2004

NWS Fairbanks, AK issued this flash flood warning at Jul 20, 2004, 4:26 PM AKDT. It was in force for 19 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 20, 2004, 4:26 PM AKDT (00:26 UTC)
Expired
Jul 21, 2004, 11:00 AM AKDT
In force
19 hr
Issued by
NWS Fairbanks, AK
Area
Counties, with a storm outline in the text

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Fairbanks, (PFAI), launched 00:00Z, 0.4 hours before the alert went out and 93 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, Fairbanks, at 00:00Z on 2004-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 407 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, Fairbanks, at 00:00Z on 2004-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 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
407 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
1320 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
22 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 
WGAK59 PAFG 210128
FFWAFG
AKZ220-222-224-210200-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE FAIRBANKS AK
926 PM ADT TUE JUL 20 2004

THE NATIONAL WEATHER SERVICE IN FAIRBANKS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  MIDDLE TANANA VALLEY AREA OF ALASKA
  UPPER TANANA VALLEY AND THE FORTYMILE COUNTRY AREA OF ALASKA
  YUKON FLATS AND SURROUNDING UPLANDS AREA OF ALASKA
  THIS INCLUDES THE CITY OF TWELVEMILE SUMMIT

* UNTIL 1000 PM ADT

* AT 924 PM ADT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM 14 MILES SOUTH OF TWELVEMILE
  SUMMIT...OR ABOUT 11 MILES NORTH OF CHENA HOT SPRINGS. THE STORM
  PRODUCING FLASH FLOODING WAS NEARLY STATIONARY.

* THE STORM PRODUCING FLASH FLOODING WILL OTHERWISE REMAIN OVER
  MAINLY RURAL AREAS OF THE INDICATED COUNTIES.

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.

LAT...LON 6512 14636 6516 14563 6544 14563 6538 14651

$$

RF/AT JUL 04

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 Fairbanks, AK wrote its last area forecast discussion before this flash flood warning went out at Jul 20, 9:50 AM AKDT, 6 hours 36 minutes earlier.

Area forecast discussion, Jul 20, 9:50 AM AKDT, 6 hours 36 minutes before
NORTH ALASKA FORECAST DISCUSSION
250 PM ADT TUE JUL 20 2004

.DISCUSSION...

.ALOFT...MAJOR FEATURES THIS AFTERNOON INCLUDE A 555 DM LOW IN THE
NORTHERN GULF OF ALASKA AND A WEAKENING TROUGH MOVING NORTH INTO
THE HIGH ARCTIC OCEAN.  IN BETWEEN THESE SYSTEMS...A RIDGE
STRETCHES EAST-WEST THROUGH THE INTERIOR. ETA AND GFS BOTH
INDICATE THE LOW IN THE GULF TO WOBBLE CLOSE TO THE COAST OVER THE
NEXT 3 TO 5 DAYS. THIS WILL ALLOW SEVERAL SHORT WAVES TO MOVE
ACROSS THE INTERIOR FROM THE SOUTHEAST OVER THE NEXT FEW DAYS. MOS
POPS INDICATE MUCH HIGHER PROBABILITIES OF CONVECTION OVER THE
INTERIOR ON WEDNESDAY. THE REMAINDER OF THE FORECAST AREA WILL BE
FREE FROM ANY MAJOR SYSTEMS AS THE OVERALL PATTERN REMAINS SIMILAR
TO THE PAST SEVERAL WEEKS.

.SURFACE...SCATTERED CONVECTION WILL BE THE RULE FOR THE NEXT
SEVERAL DAYS OVER THE INTERIOR AND WESTWARD TO THE NULATO HILLS.
THE ABOVE-MENTIONED SHORT WAVE WILL LIKELY TRIGGER CONVECTION OVER
THE HIGHER ELEVATIONS ACROSS THE INTERIOR ON WEDNESDAY. FOR THE
REMAINDER OF THE WEEK...THE THERMAL TROUGH OVER THE INTERIOR WILL
ASSIST IN CONVECTIVE DEVELOPMENT ALONG WITH A GENERAL SOUTHWEST
WIND FLOW.

.ARCTIC...THE ARCTIC COAST WILL REMAIN DRY AS THE TROUGH MOVES
WELL TO THE NORTH AND NO SIGNIFICANT SYSTEMS ON THE HORIZON. WINDS
BEHIND THIS TROUGH WILL BE FROM THE NORTHWEST FOR THE NEXT 24
HOURS THEN SHIFT TO A MORE CLIMATOLOGICALLY NORMAL EAST TO TO
SOUTHEAST DIRECTION LATE WEDNESDAY. PATCHY DENSE FOG IS LIKELY
TONIGHT AS MANY REPORTING LOCATIONS HAVE DIPPED TO LESS THAN A
MILE AT TIMES OVER THE PAST 24 HOURS.

.WESTERN COAST...QUIET WEATHER IS IN STORE FOR THIS REGION AS HIGH
PRESSURE BUILDS IN WHILE THE MAIN UPPER LOW REMAINS WELL TO THE
EAST. SCATTERED CONVECTION IS POSSIBLE OVER THE NULATO HILLS AND
OTHER ELEVATED TERRAIN THROUGH THE REMAINDER OF THE WEEK. WINDS
WILL BECOME LIGHT AS THE HIGH BUILDS OVER THE NEXT FEW DAYS WITH
TEMPERATURES NEAR SEASONAL AVERAGES.

.HYDRO...NO SIGNIFICANT ISSUES.

.FIRE WEATHER...NUMEROUS LIGHTNING STRIKES YESTERDAY ALONG WITH
MORE ACTIVITY TODAY WILL LIKELY RESULT IN NEW FIRE STARTS.
CONCERNS TODAY INCLUDE DOWNDRAFT OUTFLOW FROM CONVECTION SIMILAR
TO LAST EVENING WHEN WINDS ROUTINELY GUSTED IN THE 25 KNOT RANGE
OVER THE INTERIOR ZONES. THESE OUTFLOWS GENERALLY BLEW FROM THE
EAST ACROSS THE FIRES AND WE WOULD EXPECT SIMILAR CONDITIONS TODAY
AS CONVECTION DEVELOPS.

.AFG WATCH/WARNING/ADVISORIES...
PUBLIC...DENSE FOG ADVISORY 201 202 203 204 206 213
         DENSE SMOKE ADVISORY 216 217 218 219 220 222 224
MARINE...NONE

AT JUL 04

Nearby

Flash Flood Warnings in Alaska, 2004Every flash flood warning in 2004

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.