Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

000 
FXAK69 PAFG 232235
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
235 PM AKDT Tue Jul 23 2019

.SYNOPSIS...
Ridging over the Interior will bring warm and dry conditions over
the Interior through Tuesday. Ridging will weaken on Wednesday
but still remain warm over the eastern Interior. The main weather 
concerns for today is the growing coverage and intensity of smoke
across the Interior. Additionally, thunderstorm activity will
increase on Wednesday across the Interior. Slightly cooler 
temperatures with rain showers expected Thursday and into the 
weekend for the Interior.

&&

.DISCUSSION...
Aloft...A 575 dam ridge of high pressure has moved over Interior 
Alaska and persist through today. Ridging over the Interior will
weaken and push northward on Wednesday allowing shortwaves to 
move up from the Gulf of Alaska. This will increase shower and
thunderstorm activity over the Interior Wednesday and Thursday.
A longwave trough will deepen over the Bering Strait through 
Wednesday. This trough will push shortwaves across the Bering 
Strait through Thursday. The trough will linger over the west
coast through Friday. An easterly wave will move into the Eastern
and Central Interior Thursday evening, bringing primarily 
numerous shower activity. Temperatures will reach the low to mid 
80s across the Interior today, with cooling conditions through the
rest of the week. 
 
Surface...A 1022 mb high over the eastern Beaufort Sea will move 
to the northeast as a 1023 high by tomorrow afternoon. A 
developing 995 mb low will be south of Wrangel Island by 
tomorrow. Strong easterly winds will develop over the eastern
north slope on Wednesday and persist into Thursday. A thermal
trough will develop over the southern Interior today then move
north over the central Interior on Wednesday.

Interior...Main weather concern today is smoke over the central
Interior. Low visibility reported in many locations due to the 
smoke this afternoon. Dense smoke advisories have been extended 
out until noon Wednesday for the Delta Junction area and around 
Fort Yukon. Warm and dry condtions will continue today with 
temperatures in the low 80s. A thermal trough will develop south 
of the Alaska Range today. This setup will increase isolated 
thunderstorm coverage across the southern Interior today. As the 
high pressure slides further northeast, the thermal trough will 
move north over the central Interior tomorrow. As a result, 
thunderstorm activity will increase across the Interior on 
Wednesday, with widely scattered thunderstorms possible in areas 
around Tanana. An easterly wave will move into the Eastern and 
Central Interior on Thursday, bringing primarily widespread shower
activity. Models differ on the exact timing of this wave but
general consensus of the rain for the central Interior is late
Thursday afternoon into the evening hours. Cooler temps and
chances of rain will continue into the weekend.

North Slope and Brooks Range...Easterly flow will persist through
Thursday. Expect low ceilings and periodic low visibility to 
return from Utqiagvik and east. Winds will be strong as well
around 25 to 40 mph along the eastern north slope. Isolated 
thunderstorms are possible in the central and eastern Brooks 
Range for the tomorrow and Thursday. 

West coast...Low stratus and fog expected to persist over the
Bering strait today. A weather front will push east into St. 
Lawrence Island, with rain showers likely this evening. 
A strong low pressure system will move north to St. Lawrence 
Island by Thursday morning, pushing a strong front across
the west coast bringing widespread showers on Thursday.

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

&&

.FIRE WEATHER...
Main fire weather concern today is smoke over the central 
Interior. Low visibility reported in many locations due to the 
smoke this afternoon. Dense smoke advisories have been extended 
out until noon Wednesday for the Delta Junction area and around 
Fort Yukon. A thermal trough will develop over the southern 
Interior today and will be the focus for isolated thunderstorms
as well. The thermal trough will move north over the central 
Interior tomorrow. As a result, thunderstorm activity will 
increase across the Interior on Wednesday, with widely scattered 
thunderstorms possible in areas around Tanana. On Thursday, the 
best chance of thunderstorms willl be from Fort Yukon to the 
eastern Brooks range. An easterly wave will bring widespread 
showers into the Interior on Thursday, with increased chances for 
wetting rains. Temperatures expected to peak today and then 
decrease for the rest of the week in the Interior, with minimum RH
improving.

&&

.HYDROLOGY...
Expect glacier-fed rivers to remain elevated through this week due
to increasing temperatures. Otherwise, relatively dry conditions
should keep rivers at their current levels.


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Dense Smoke Advisory for AKZ220-AKZ223.

Small Craft Advisory for PKZ230-PKZ235-PKZ240-PKZ245.

National Weather Service Glossary of Abbreviations