Alert archive / Alaska / Flash Flood Warnings in 2007

Flash Flood Warning 2, NWS Fairbanks, AK

April 24, 2007

NWS Fairbanks, AK issued this flash flood warning at Apr 24, 2007, 6:57 AM 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
Apr 24, 2007, 6:57 AM AKDT (14:57 UTC)
Expired
Apr 25, 2007, 1:30 AM AKDT
In force
19 hr
Issued by
NWS Fairbanks, AK
Area
Counties, with a storm outline in the text
Flood severity
None

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

Point Barrow, (PBRW), launched 12:00Z, 3.0 hours before the alert went out and 240 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, Point Barrow, at 12:00Z on 2007-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Point Barrow, at 12:00Z on 2007-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
485 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
42 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 241959
FFWAFG
AKZ205-242030-
/T.NEW.PAFG.FF.W.0001.070424T1957Z-070424T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
TEST...FLASH FLOOD WARNING...TEST
NATIONAL WEATHER SERVICE FAIRBANKS AK
1157 AM ADT TUE APR 24 2007

...THIS MESSAGE IS FOR TEST PURPOSES ONLY...

THE NATIONAL WEATHER SERVICE IN FAIRBANKS HAS ISSUED A

* THIS IS A TEST MESSAGE. FLASH FLOOD WARNING FOR IVOTUK CREEK

* UNTIL 1230 PM ADT

* THIS IS A TEST MESSAGE. AT 1154 AM ADT...NATIONAL WEATHER SERVICE
  DOPPLER RADAR INDICATED FLASH FLOODING FROM A THUNDERSTORM OVER THE
  WARNED AREA.

* THIS IS A TEST MESSAGE. THE STORM PRODUCING FLASH FLOODING WILL   
OTHERWISE REMAIN OVER THE IVOTUK HILLS.

THIS IS A TEST MESSAGE. 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.

THIS IS A TEST MESSAGE. DO NOT TAKE ACTION BASED ON THIS MESSAGE.

LAT...LON 6917 15885 6917 15834 6935 15834 6935 15885

$$

EWP
1 follow-up statement
000 
WGAK79 PAFG 242020
FFSAFG

TEST...FLASH FLOOD STATEMENT...TEST
NATIONAL WEATHER SERVICE FAIRBANKS AK
1220 PM ADT TUE APR 24 2007

...THIS MESSAGE IS FOR TEST PURPOSES ONLY...

AKZ205-242030-
/T.CAN.PAFG.FF.W.0001.000000T0000Z-070424T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NORTHWESTERN BROOKS RANGE AK-
1220 PM ADT TUE APR 24 2007

...THIS MESSAGE IS FOR TEST PURPOSES ONLY...

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR IVOTUK CREEK...

THIS IS A TEST MESSAGE. DO NOT TAKE ACTION BASED ON THIS MESSAGE.

LAT...LON 6917 15885 6917 15834 6935 15834 6935 15885

$$

EWP

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 Apr 24, 12:36 AM AKDT, 6 hours 21 minutes earlier.

Area forecast discussion, Apr 24, 12:36 AM AKDT, 6 hours 21 minutes before
NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
536 AM ADT TUE APR 24 2007

.DISCUSSION...

WEAK FLOW PATTERN ALOFT PERSISTING OVER THE FORECAST AREAS
FOR THE NEXT WEEK. LITTLE TEMPERATURE CHANGE IS EXPECTED
IN THE LOWER LEVELS.

12Z SURFACE MAP SHOWING WEAK TROUGH BETHEL-30 S TANANA-
FAIRBANKS-EAGLE AND WEAK RIDGING OVER THE EASTERN NORTH
GULF COAST. GRADIENT ACROSS THE ALASKA RANGE IS WEAK BUT
PROBABLY ENOUGH FOR SOUTH WINDS GUSTING TO 15 MPH IN ALASKA
RANGE PASSES DEVELOPING BY MID DAY.

SATELLITE LOOP PICKING UP WEAK VORT CENTER NORTH OF
PAOR...THIS FEATURE WILL LIKELY PRODUCE SCATTERED
RAIN SHOWERS OVER THAT AREA TODAY.

ELSEWHERE IN THE INTERIOR...WEAK INSTABILITY WITH
ISOLATED AFTERNOON AND EVENING SHOWERS TODAY AND
AGAIN WEDNESDAY. THE INSTABILITY IS EXPECTED TO
SPREAD TO MUCH OF THE WEST COAST WEDNESDAY...CONTINUING
THURSDAY.

NORTHEAST WINDS TYPICALLY 10-20 MPH ARE EXPECTED
TO DEVELOP OVER MUCH OF THE INTERIOR AS THE TROUGH
NOW OVER THE CENTRAL INTERIOR DISSIPATES AND THE WIND
FLOW BECOMES MORE ORGANIZED BETWEEN HIGH PRESSURE OVER
THE ARCTIC AND A STRONG LOW PROGGED TO MOVE INTO THE GULF
OF ALASKA.

WINDS OVER THE ARCTIC COAST WILL REMAIN OUT THE EAST
OR NORTHEAST AND INCREASE A LITTLE. CLOUDY CONDITIONS
WITH SCATTERED FLURRIES AND AREAS OF FOG WILL CONTINUE.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.FIRE WEATHER...
MAX TEMPERATURES AND MIN RH TODAY EXPECTED TO BE SIMILAR
TO CONDITIONS EXPERIENCED YESTERDAY. LITTLE CHANGE IS
EXPECTED WEDNESDAY. WINDS WILL HAVE TO BE WATCHED THURSDAY
AS SOME SITES MAY GUST TO AROUND 25 MPH.

&&

.HYDROLOGY...
NONE.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FOR AKZ223-AKZ225.

BRISK WIND ADVISORY FOR PKZ210-PKZ230-PKZ235-PKZ240-PKZ245.
&&

RF APR 07

The office that day

Everything else NWS Fairbanks, AK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 23, 9:42 PM AKDTBrisk Wind AdvisoryAFG11 hr
Apr 24, 8:39 AM AKDTHeavy Freezing Spray WarningAFG32 hr

Nearby

Flash Flood Warnings in Alaska, 2007Every flash flood warning in 2007

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.