Update on Major Storm System Expected to Bring Heavy Rain and Strong Winds to Much of the Southern Alaska Mainland this Upcoming Week

...UPDATE ON MAJOR STORM SYSTEM HEADED FOR THE SOUTHERN ALASKA 
MAINLAND...

A MAJOR STORM REMAINS ON TRACK TO BRING HEAVY RAIN AND STRONG
WINDS TO MUCH OF THE SOUTHERN MAINLAND DURING THE EARLY TO MIDDLE
PART OF THIS WEEK. THERE IS A LARGE SPREAD IN THE LATEST FORECAST 
GUIDANCE ON THE TRACK OF KEY FEATURES WITH THIS VERY LARGE SYSTEM.
THUS...FORECAST CONFIDENCE IS LOW FOR MANY OF THE DETAILS OF
TIMING AND LOCATION OF HEAVIEST RAIN AND STRONGEST WINDS. THERE 
IS HOWEVER ENOUGH CONFIDENCE IN SOME OF THE MORE LIKELY IMPACTS.
AS OF SUNDAY AFTERNOON THE FOLLOWING HAZARD PRODUCTS HAVE BEEN
ISSUED.


...HIGH WIND WATCH IN EFFECT FROM TUESDAY EVENING THROUGH
WEDNESDAY EVENING ALONG TURNAGAIN ARM AND HIGHER ELEVATIONS...

...HIGH WIND WATCH IN EFFECT FROM TUESDAY EVENING THROUGH
WEDNESDAY EVENING THROUGH PORTAGE VALLEY AND TURNAGAIN ARM...

SOUTHEASTERLY WIND GUSTS OF 65 TO 80 MPH ARE POSSIBLE FOR THESE
AREAS.


...HIGH SURF ADVISORY IN EFFECT FROM 1 PM TO 7 PM AKDT MONDAY 
FROM KUSKOKWIM BAY TO HOOPER BAY...

HIGH SURF WITH POTENTIAL FOR COASTAL EROSION IS EXPECTED ALONG
SOUTH FACING SHORES.


THERE IS ALSO HIGH CONFIDENCE IN THE MARINE FORECASTS FOR THE
GULF OF ALASKA NORTHWARD TO PRINCE WILLIAM SOUND...WITH WIDESPREAD
GALE TO STORM FORCE WINDS TUESDAY NIGHT THROUGH WEDNESDAY. 

THE GREATEST AREA OF UNCERTAINTY WITH THE UPCOMING STORM IS THE
TRACK OF A SECONDARY SURFACE LOW ON TUESDAY NIGHT FROM SOUTH OF
KODIAK ISLAND AND THE ALASKA PENINSULA UP TO INTERIOR SOUTHWEST
ALASKA. FORECAST GUIDANCE SHOWS A 300 MILE SPREAD IN WHERE THIS
LOW WILL TRACK. THIS LEADS TO VERY LOW FORECAST CONFIDENCE ACROSS
THE WESTERN GULF/KODIAK ISLAND UP TO COOK INLET AND INTO PORTIONS
OF INTERIOR SOUTHWEST ALASKA.

DEPENDING ON THE TRACK OF THE SURFACE LOW...THERE IS THE 
POSSIBILITY THAT STRONG WINDS COULD AFFECT LOWER ELEVATIONS OF
THE KENAI PENINSULA...ANCHORAGE...AND THE MATANUSKA VALLEY
SOMETIME WEDNESDAY. THIS POTENTIAL ALWAYS WARRANTS CLOSE
MONITORING DURING THE FALL SEASON WHEN THE PRESENCE OF LEAVES ON
THE TREES AND UNFROZEN SOILS CAN LEAD TO MUCH GREATER IMPACT FROM
STRONG WINDS COMPARED WITH SIMILAR WINDS IN THE MIDDLE OF WINTER.
THE TRACK OF THE LOW WILL ALSO DETERMINE WHICH AREAS WILL SEE THE
HEAVIEST RAIN AND BE MOST SUSCEPTIBLE TO FLOODING.

STAY TUNED TO LOCAL MEDIA AND NATIONAL WEATHER SERVICE FORECASTS
FOR MORE DETAILS ON THIS APPROACHING FALL STORM. THE LATEST
FORECAST AND WARNINGS ARE ALWAYS AVAILABLE AT WWW.WEATHER.GOV/AFC