Small Craft Advisory 67, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
420 AM AKDT Tue Jul 3 2018

.DISCUSSION...
The ridge that has built in over much of the state will be the
driver of weather for most of the state this week. A low will
skirt across the Arctic over the top of the ridge, producing
inclement weather for the North Slope. The main weather concern
over the next few days will be the low pressure system moving
across the Arctic. Secondarily, fire weather is of slight concern
due to warming and drying from the ridge coupled with people
outdoors celebrating Independence Day. However, conditions are not
expected to dry too much, so this is of lesser concern.

Models generally agree with the solution through Thursday on the
overall pattern, then they begin to differ considerably going into
the weekend. All models have an upper level low coming into play
over the weekend for the Interior. However, the GFS exits this
low and builds ridging back in, while the ECMWF keeps the low as a
stronger presence through the weekend. As a result, not much
confidence in the long range right now.

Aloft...
The longwave ridge is building as expected from the south. This
ridge will remain the main influencer for the Interior and West
Coast the next few days. An upper level low moves south and east
across the Arctic the next couple of days, flattening the ridge
somewhat. The center of this low is expected to move along the
coast and past Demarcation Point Thursday afternoon. As is does
this a trough will push southeast through the Interior, cooling
temperatures and producing some showers and thunderstorms ahead
of it. Beyond this point in time is when models begin to diverge.

Surface...

Central and Eastern Interior...
High pressure will be the dominant feature until Thursday. Warm
and dry conditions will be present over the holiday as a result.
Conditions are not expected to dry to the point of meeting Red
Flag criteria. However, warming and drying will increase the fire
threat the next couple of days, so those going outdoors for the
holiday should be careful with open flames of any kind. The front
mentioned above is expected to push through the Interior on
Thursday afternoon, bringing some showers, thunderstorms and
cooler temperatures with it. It is not anticipated to be a major
weather producer though. Even with the high, some isolated
thunderstorms are possible today in the Eastern Brooks Range and
tomorrow in the southeast Interior.

West Coast and Western Interior...
The West Coast and Western Interior are pretty quiet when it comes
to major weather features with high pressure directly over them.
However, with high pressure in place this time of year, there is
persistent sea stratus and sea fog in areas immediately along the
coast. Rain showers will be present in the Southwest Interior and
in the Y-K Delta Wednesday and Thursday. The tail end of the front
that is expected to move southeast through the North Slope and
Interior Wednesday into Thursday will bring a few showers to the
Western Interior and West Coast as well, though it will quickly
die out as it goes. So, no major impacts for the West Coast.

North Slope and Brooks Range...
Inclement weather will be present the next few days with a low
pressure system working its way from west to east across the
North Slope. The low should impact the northwest coast today and
the eastern north slope tomorrow. Low ceilings, windy conditions
and showers are expected for most areas. Temperatures are warm
enough that precipitation should fall in the form of rain. Behind
the front, a tight pressure gradient will produce strong northwest
winds. The Brooks Range will also see rain from this system,
mainly in the central and eastern Brooks Range.

Coastal Hazard Potential Days 3 and 4...
Strong northerly winds may cause elevated surf in areas of the
northwest coast that is free of shore ice.

&&

.FIRE WEATHER...
Isolated convection may be possible today in the Eastern Brooks
Range and tomorrow in the Southeast Interior. Otherwise thunderstorm
activity will quiet as a strong ridge will continue to build
through much of the state. This ridge will also produce warming
and drying throughout the Interior the next couple of days. One
area of concern is the Northeast Interior, mainly in the Yukon
Flats. We will need to keep an eye on possible Red Flag conditions
there for the next couple of days.

&&

.HYDROLOGY...
Periods of heavy precipitation that occurred in the Southeast
Interior over the weekend are still influencing river levels.
River levels are expected to remain high for the next several days
as the rain that fell continues to work its way through various
watersheds. Glacial melt with warming temperatures during the week
will also contribute to high water levels. Water is also expected
to remain over the Tetlin Road through the week.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory for PKZ210-PKZ220-PKZ225-PKZ235.

Gale Warning for PKZ230.
&&

BJB JUL 18