A storm force low in the western Gulf of Alaska developed down to 964 MB off Kodiak on the evening of Monday September 19th with an associated occluded front moving to the eastern Gulf Coast by Tuesday evening. A secondary low developed well to the south of the main center.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS AJK wrote it up.
A storm force low in the western Gulf of Alaska developed down to 964 MB off Kodiak on the evening of Monday September 19th with an associated occluded front moving to the eastern Gulf Coast by Tuesday evening. A secondary low developed well to the south of the main center. This low became storm force 961 MB early on the morning of Wednesday the 20th off the Queen Charlottes and started to curve back into the central Gulf. The pressure gradients became extreme around this system by midday causing hurricane force winds for several coastal regions of the Panhandle on Wednesday. This storm dissipated rapidly later Wednesday afternoon.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Juneau, AK wrote its last area forecast discussion before the first event at Sep 21, 4:36 AM AKST, 6 hours 16 minutes earlier.
SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
536 AM AKDT WED SEP 21 2011
.SHORT TERM...EARLY MORNING SATELLITE IMAGES REVEAL A DEEPENING
LOW...ABOUT 968 MB...WELL WEST OF HAIDA GWAII WITH AN OCCLUDED
FRONT ORGANIZING IN THE FAR SOUTHEASTERN GULF. CONSOLIDATED
CLOUDS AND RAIN BANDS WRAPPING AROUND THE LOW CONTINUE BRING
MODERATE TO HEAVY RAINFALL ACROSS THE EASTERN GULF AND THE
PANHANDLE. AHEAD OF THE INCOMING FRONTAL PASSAGE...STRONG
SOUTHEAST WINDS HAVE BEGUN OVER THE SOUTHERN COASTAL AREAS. WITH
INCREASING SOUTHEAST WINDS...LOCAL WIND WAVES BECAME ROUGH UP TO
20 FEET OVER THE SOUTHERN OUTER WATERS.
MODELS ARE IN FAIR AGREEMENT WITH THE 968 MB LOW MOVES NORTH TO
OFFSHORE SITKA THIS MORNING THEN CONTINUES DRIFTING NORTH AND
WEAKENS TO ABOUT 974 MB SOUTH OF YAKUTAT BAY IN THE AFTERNOON. THE
LOW IS EXPECTED TO DISSIPATE RAPIDLY DURING THE EVENING AS A WEAK
RIDGE OF HIGH PRESSURE BUILDS ACROSS SOUTHEAST ALASKA TONIGHT. THE
GFS INITIALIZED THE BEST AND WAS USED TO REFRESH THE INHERITED
GRIDS FOR TODAY AND TONIGHT. MAINTAINED CATEGORICAL POPS FOR
ENTIRE FORECAST DOMAIN THROUGH TONIGHT WITH RAINFALL HEAVY AT
TIMES AND SMALL DIURNAL TEMPERATURE FLUCTUATIONS.
LOCAL STREAMS AND RIVERS WILL CONTINUE TO RISE STEADILY IN
RESPONSE TO THE MODERATE TO HEAVY RAINFALL THROUGH TONIGHT.
HOWEVER...NONE OF THE STREAMS OR RIVERS WILL REACH THEIR ACTION
STAGES. AS THE LOW DRIFTS NORTH RELATIVELY FAST THROUGH THIS
AFTERNOON...STORM FORCE WINDS WILL CONTINUE TO SPREAD NORTHWARD
RAPIDLY ACROSS THE OUTER WATERS THIS MORNING THEN EASE TO GALE
FORCE THIS AFTERNOON AND EVENING HOURS...AND FURTHER DOWN TO SMALL
CRAFT WINDS THROUGH TONIGHT.
.LONG TERM...N PACIFIC EXPLOSIVE CYCLOGENESIS THU WILL RESULT IN
A 958 TO 962 MB LOW 120 NM SW OF PAKT ABOUT 06Z FRI. THE LOW WILL
TRACK N TOWARD PASI AND BEGIN TO FILL BEFORE LANDFALL EARLY FRIDAY.
PLEASE NOTE THE HIGH WIND WATCHES SHOWN IN THE TABLE BELOW. GUSTS
OF 60 MPH ARE LIKELY TO OCCUR WITH THIS SYSTEM AND THE CONFIDENCE
FOR THIS EVENT REACHING THIS VALUE FOR LOCATIONS WITHIN THOSE ZONES
IS BETWEEN 60 AND 80 PERCENT.
ZONAL-TRACKING WV IS 700 NM S OF PACD ATTM, AND CONTG TO MOV ALONG
A HIGHLY BAROCLINIC SECTION OF POLAR FRONT ZONE. BOMB DEEPENING
FROM 992 MB 1000 NM S OF PAMD AT 06Z THU TO ABT 962 MB 120 NM SW
OF PAKT 06Z FRI. THE RSLTG LOW HAS A COMPACT CIRCULATION THAT IS
AT THE SMALL FOR A SYNOPTIC SCALE FEATURE. THE MODEL CONSENSUS FOR
THIS SYSTEM HAS BEEN POOR UNTIL RECENT RUNS. HWVR THE GFS RUNS
HAVE ADJUSTED TO THE EC. FROM 21.00 TO 21.06 THE GFS BECAME CLOSE
TO THE 21.00 EC FOR LIFE-CYCLE AND TRACK OF THIS EXPLOSIVE
CYCOGENESIS.
.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING FOR
AKZ023-027-028.
MARINE...STORM WARNING FOR PKZ041>043.
GALE WARNING FOR PKZ021-022-031>036-051.
SMALL CRAFT ADVISORY FOR PKZ011>013-052-053.
&&
AHN/JBT5 high wind. Local standard time, as filed.
Sitka Airport (PASI) ASOS recorded numerous gusts 60 to 65 MPH on the afternoon of Wednesday, September 21st.
Nearby marine observation Sisters Island had peak gusts to 56 KT on Wednesday 9.21.|Nearby marine observation Cape Spencer had peak gusts to 70 KT on Wednesday 9.21.|Strongest winds for the Gustavus area would have occurred at the State Ferry Dock. Impact was that the ferry could not land that day.
Nearby marine observation Sisters Island had peak gusts to 56 KT on Wednesday 9.21.
Nearby marine observation Sisters Island had peak gusts to 56 KT on Wednesday 9.21.|Nearby marine observation Cape Spencer had peak gusts to 70 KT on Wednesday 9.21.
Juneau Airport ASOS had a measured gust of 62 KT around 1300 AKST on Wednesday 9.21.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2011Every state in 2011This day in weather historyWarnings in Alaska, September 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 351942, 351943, 351944, 351946, 351947.