Scientific Forecaster Discussion
fxus65 kfgz 261633
Area forecast discussion
National Weather Service Flagstaff Arizona
933 am MST Wed Jun 26 2019
Synopsis...gusty southwest winds, near normal temperatures and
mainly dry conditions will persist through Friday. Critical fire
weather conditions are expected for portions of north central and
northeastern Arizona each day. A chance for afternoon thunderstorms
will return to eastern Arizona towards the end of workweek with
continued near normal temperatures.
Update...satellite imagery shows sunny to mostly sunny skies
across much of northern Arizona this morning. The high level
clouds will continue to move northeastward with the southwesterly
flow that strengthened overnight. Surface winds are already
gusting upwards of 30 mph in portions of Coconino and Yavapai
counties. These gusty winds will become more widespread across all
of northern Arizona into this afternoon. Due to low relative
humidity values, gusty winds and dry fuels, a red flag warning
remains in effect from 1 PM through 6 PM MST today for some areas
east of Flagstaff. Sky cover was increased in the morning
forecast update for portions of the high country to account for
the high level clouds through the daytime hours.
Previous discussion /342 am MST/...strong low pressure off the coast
of Oregon will keep a dry southwesterly flow over Arizona through
Friday. Scattered high level clouds continue to stream across the
state this morning, and will gradually decrease through the day.
The Pacific northwest low makes little movement over the coming
days which will keep Arizona in this dry, warm and breezy pattern
through Friday. A red flag warning is in effect day for critical
fire weather conditions across a portion of north-central and
northeastern Arizona. Similar areas will see near critical fire
weather on Thursday, and perhaps Friday as well.
Consensus among operational model runs and ensemble means this
morning shows a slightly better increase in moisture across the
area this weekend, particularly Saturday and Sunday. Much of this
may come in the form of cloud cover, which will inhibit
thunderstorm chances. It appears rain and thunderstorms chances
will still favor eastern Arizona, but stay tuned to the forecast
as things can change quickly this time of year. Temperatures will
warm close to or slightly above average over the weekend and
remain so into next week.
The chance for afternoon thunderstorms will continue for the
mountainous regions along the New Mexico border early next week.
There continues to be spread in how the models resolve the pattern
next week, but at this point the consensus points toward a drier
southwest flow developing as a persistent trough remains over the
Aviation...for the 18z package...expect VFR conditions through this
forecast period. Sfc winds S-sw10-20g30kts through 02z then
decreasing. Local visibility restrictions possible due to wildfire
smoke. Aviation discussion not updated for taf amendments.
Fire weather...dry, warm and breezy conditions will persist
today and Thursday. A red flag warning has been issued for portions
of central and eastern Arizona this afternoon. Critical fire weather
conditions are likley in roughly the same areas again on Thursday
Friday through Sunday...dry and warm weather, with continued gusty
southwest winds, will continue on Friday. This will produce some
areas of critical fire weather conditions on Friday afternoon. An
increase in moisture, along with a slight downturn in southwesterly
wind speeds, will diminish the chance of reaching these thresholds
Saturday and Sunday. However, there will be a threat of high-based
convection across the eastern and some central zones by the weekend.
Fgz watches/warnings/advisories...red flag warning from 1 PM this afternoon to 6 PM MST this
evening for azz112-113-116-140.