Northern Alaska forecast discussion...corrected
National Weather Service Fairbanks Alaska
132 PM akdt Sat may 25 2013
Discussion...
models in good agreement through early week on large scale
features through next week with upper level high pressure ridge
building west out of Canada over Mainland Alaska. Warm
temperatures will continue over the eastern and central interior
through the weekend and will continue to expand westward into
early next week. There are minor differences with strength and
timing on a weak short wave moving north out of the northern
Pacific and moving into the central and eastern interior Sunday
and another weak short wave moving northwest into the western
interior Monday. Convective parameters look better for producing
isolated showers or thunderstorms in the central and eastern
interior with lifted index around minus 2 however best cape with
values around 500 near the Canadian border. NAM seems to be the
odd model with upper level energy moving into western interior
Monday afternoon with lifted index around -2 and cape values
topping out near 400 near Galena.
Forecast focus continues to be on hydrological issues on several fronts.
The warm air mass building into the eastern and central interior is
causing rapid melt off of a still sizable snow pack above 2500 feet
into small streams and rivers across the interior. Elevated water levels
are noted on the Chatanika...upper chena...the little chena and
the Salcha rivers. Flood Warning issued this morning on reports of
large and quick water rises as well as reports of large chunks of
ice moving down the Salcha river. Will continue to monitor situation
closely with increased activity on and near area rivers over
Memorial Day weekend.
The ice breakup front on the river Yukon has moved approximately 50
miles down river from Tanana where the Flood Watch has been
cancelled. The ice jam just down river from the McGrath Airport
released this morning with water levels falling at McGrath. Flood
Watch was cancelled for McGrath as well.
&&
Fire weather...
relative humidity values will be low over portions of the eastern interior with
red flag warnings hoisted for zone 220 223 and 224.
&&
Hydrology...
warm temperatures will continue across the interior with freezing
levels above 7 kft. Rapid melt off of snow pack above 2500 feet will
continue to keep water levels high on interior rivers.
&&
Afg watches/warnings/advisories...
red flag warning for akz220-akz223-akz224.
Flood Warning for ak222-ak223-ak224.
&&
$$
Ccc may 13
