048
FXAK69 PAFG 022208
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
208 PM AKDT Thu May 2 2024

.SYNOPSIS...
Upper-air analysis this afternoon is showing a trough of low
pressure moving from the Alaska Peninsula into the southern Gulf of
Alaska. At the same time, a deep trough is moving into the western
Bering Sea this afternoon. To the north, in the Arctic Ocean, there
is a low pressure system in the eastern half with high pressure over
the western half. The low pressure system is impacting more of the
Northern Slope than the high pressure is at this time. Not much
change to the upper-air pattern as we move further into the weened
and into next week for the Northern Slope. The same cannot be said
about the systems moving through the Bering Sea and Gulf of Alaska.
The first trough will dig southeast into the Pacific Northwest by
early Saturday morning while the second trough will be approaching
the Alaska Peninsula. This secondary trough will be deeper than
average at around 512mb. This low will eventually push into the Gulf
of Alaska late weekend into early next week.

&&

.DISCUSSION...
The pattern will be favorable for the Northern Slope to remain much
cooler than normal with some flurries or light snow and fog to
remain in place through the weekend. Precipitation chances will
increase across the Northern Slope towards late weekend as scattered
rain and snow showers will develop from pretty much the YK Delta to
far northeast Alaska. Increased precipitation chances will remain in
place heading into the start of next week.

The West Coast will remain dry and cold with increasing wind as we
head into the weekend. Winds really increase by Saturday from the
Lisburne Peninsula south through the Seward Peninsula and into the
Norton Sound. While the West Coast region will remain dry through
Friday, the same energy that will bring increased chances to the
north will bring increased chances of precipitation through the day
Saturday and Sunday morning. There was some internal discussion
today about the potential for some blowing snow across the West
Coast that could lead to some headlines later this weekend, however,
due to some of the warmer weather across this area, it might be hard
to get some blowing snow out there that could prevent any headlines
later this weekend.

The Western Interior will generally remain dry and cold through the
weekend with increasing precipitation chances from the same energy
impacting the rest of the area. The Eastern Interior will be drier
and slightly warmer as we move into the weekend. In addition, winds
will increase late Friday and into Saturday for the Alaska Range and
Delta Junction area as strong south winds will set up. There will
also be some increased precipitation potential through much of the
weekend and even into next week as the deep trough moves through
the Gulf of Alaska. There was some thought that with the increased
rainfall potential through early next week across the interior along
with the melting snow and ice break up could lead to some additional
flooding concerns. Overall, I think it could be something to watch,
but not something to go all in right now as there is some uncertainty
about how much precipitation we will get. So something we will keep
our eyes on over the next few days.

Coastal Hazard Potential Days 3 and 4...None.

&&

.FIRE WEATHER...
Main fire weather concern will be the potential for some moderate
southerly Chinook winds developing across the Alaska Range late
Friday that will continue into Saturday before diminishing by
Saturday night and into Sunday. South winds will gust to around 25
to 30 mph along the north side of the Alaska Range by Friday
afternoon, increasing to around 40 mph by Friday night into Saturday
morning. At the same time, a thermal low pressure trough will be in
the process of moving northward into the Alaska Range on Friday.
This will help temperatures increase and help RH values fall to
around the 30 percent range. Mixing the warmer temperatures, lower
RH values, and the gusty winds will bring near Red Flag conditions
from the Delta Junction south from Friday afternoon into at least
Saturday morning with a higher potential for Red Flag conditions
through the day Saturday.

&&

.HYDROLOGY...
The Flood Watch for the Tanana River near Manley Hot Springs was
cancelled this morning as the river at the Manley HS Slough went
from around 14.5 ft to 11.24 ft in a day. Because of this, it
appears that the ice jam is no longer expected to pose a threat.

Meanwhile, there remains some concern still for the Yukon River
upstream of Yukon. An observer said that the river broke up
yesterday afternoon and ice began flowing. It was reported that
within a few hours the river had stopped flowing and an ice jam had
formed. The Yukon rose to near mid-summer high levels and was
continuing to rise slowly. With the ice still in place this morning,
we have kept the SPS in place for the Fortymile Country that
includes Eagle, Chicken, and the Taylor Highway.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ802.
     Brisk Wind Advisory for PKZ803.
     Small Craft Advisory for PKZ804.
     Brisk Wind Advisory for PKZ805.
     Small Craft Advisory for PKZ806.
     Heavy Freezing Spray Warning for PKZ806.
     Brisk Wind Advisory for PKZ807-810-811-856-857.
     Brisk Wind Advisory for PKZ812-858.
     Gale Warning for PKZ816.
     Heavy Freezing Spray Warning for PKZ816.
     Gale Warning for PKZ817-851-854.
     Brisk Wind Advisory for PKZ850-853.
     Brisk Wind Advisory for PKZ852.
&&

$$

BT