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Area forecast discussion 
National Weather Service Flagstaff Arizona
855 PM MST Thursday Oct 30 2014

Synopsis...a departing high pressure ridge will bring above normal
temperatures to Arizona on Halloween. By this weekend...windy and
colder weather will develop as a Pacific cold front moves through
Arizona. This system will bring a few rain showers on Saturday and
higher chances for rain...and snow below 7000 feet on Sunday. Dry
weather returns on Tuesday with a slow warming trend.


Discussion...a departing high pressure ridge will bring warmer
temperatures and breezy winds to Arizona on Halloween. Breezy winds
will continue into the evening hours keeping temperatures above
normal for the Halloween evening festivities. A slight chance for a
few thunderstorms remains in the forecast across portions of
northeastern Arizona.

On Saturday...stronger winds are forecast ahead of a Pacific cold
front with increasing rain showers through Sunday. A dusting of
snowfall is also forecast on Sunday for portions of the high country
with snow levels dropping below 7000 feet elevation in some areas.


Previous discussion...Saturday and Sunday...strong winds are the
main story on Saturday as the initial portion of the western trough
affects the area. The Doney Park area could see wind gusts exceeding
40 miles per hour as early as Friday night into Saturday morning. By middle
morning...widespread south to southwest winds of 15 to 30 miles per hour and
gusts from 35 to 50 miles per hour are expected...with the strongest winds
along and north of the Mogollon Rim. Areas of blowing dust are
possible across the Navajo nation. As far as precipitation GOES this
weekend...we will have decent dynamics and increased moisture along
and behind the cold front Saturday...but a relatively warm layer
aloft will limit the chance of precipitation. Precipitation chances are
generally 10-20 percent Saturday for most of the Northland...but
around 40 percent on the Kaibab Plateau.

Models are in good agreement that the main trough and colder air
aloft will move into the region late Saturday night through Sunday.
The chance of showers increases for this time frame as middle level
instability increases. Snow levels could fall to around 7000 feet or
just below on Sunday. Some light accumulation possible over the
Kaibab Plateau and the San Francisco peaks. Daytime temperatures
will be the coldest of the season...not getting out of the 40s for
the mountains.

Monday through Thursday...models have slowed the departure of the
trough and cold airmass out of a slight chance of
showers continues Monday with well below normal temperatures. A slow
warming trend in daytime temperatures starts Tuesday and continues
through the week. However...overnight lows are likely to be the
coldest of the year so far...freezing temperatures possible down to the
4500 feet elevation level.


Aviation...for the 06z package...expect VFR conditions and light
winds under periodic high level clouds through Friday morning. South
winds will increase after 17z Friday becoming 15-20 kts with gusts of
25-30 kts. There will be a slight chance of -shra/-tsra from Kayenta
to Payson eastward Friday afternoon. Aviation discussion not updated
for amendments.

Fgz watches/warnings/advisories...none.




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