Area forecast discussion
National Weather Service Flagstaff Arizona
805 PM MST Sat may 25 2013
Synopsis...a broad low pressure system will remain over the Pacific
northwest through Memorial Day. This will produce gusty afternoon
winds and dry conditions across northern Arizona. A low pressure
system is forecast to affect the southwest by Tuesday and Wednesday
of next week...with cooler temperatures and a chance of showers or
thunderstorms.
&&
Discussion...dry southwest flow aloft continues this evening and
pattern not expected to change much for the next few days. Surface
winds decreasing with nocturnal cooling and decoupling this
evening...to return Sunday morning with daytime heating. Seasonably
cool temperatures expected tonight...and seasonably warm Sunday
afternoon. Current forecast is in good shape and no updates are
needed this evening.
&&
Previous discussion/330 PM MST/...dry southwest flow continues to
affect Arizona as a large area of low pressure spins over the
Pacific northwest. This pattern will continue to bring dry and mild
weather to the Northland through Memorial Day with temperatures
running very close to seasonal normals. More high level cirrus
clouds have developed today and will continue to work eastward
across the area tonight...though are not expected to be particularly
thick. Wind speeds Sunday will be very similar to this
afternoon...with gusts around 25-35 miles per hour. Slightly less wind is
expected on Memorial Day.
A piece of energy currently sitting up in the Gulf of Alaska will
reinforce the Pacific northwest low late Monday...and then drop
south into the southern Great Basin and southwest Tuesday and
Wednesday. There is still some uncertainty in just how deep the
trough will be and subsequent temperature and precipitation impacts.
Believe a blend between the GFS/European model (ecmwf) is still the best Route as the
last two runs of the European model (ecmwf) are slowly trending away from the colder
closed low solution. Thus...a trend toward cooler temperatures and a
chance for shower/thunderstorm activity can be expected for the
Tuesday/Wednesday time frame.
A large trough looks to settle over the western U.S. For late next
week. Arizona will remain on the southern periphery of this trough
resulting in a moderate westerly flow with breezy winds and close to
normal temperatures.
&&
Aviation...for the 06z package...expect VFR conditions with light
cirrus cover for the next 24 hours. Light winds until 17z...becoming
sw10-20g20-30kt until 03z Monday. Aviation discussion not updated
for amendments.
&&
Fire weather...persistent low pressure off the Pacific northwest
coast will bring continued daytime winds and dry conditions to the
district Sunday and Monday. In general...wind speeds will not exceed
critical fire weather criteria. However...a few locations will
briefly exceed these critical thresholds each afternoon.
Tuesday through Thursday...a cold front will move into the Great
Basin Tuesday and Wednesday. This front will continue to bring windy
conditions to the area...but also will bring cooler temperatures and
a chance of rain showers. Cool...drier...but continued windy
conditions are expected by Thursday.
&&
Fgz watches/warnings/advisories...none.
&&
$$
Public.........Djo/MCS
aviation.......djo
fire weather...Peterson
For northern Arizona weather information visit
weather.Gov/Flagstaff
