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Area forecast discussion 
National Weather Service Great Falls Montana
229 PM MST Wed Mar 4 2015


Tonight through Friday...forecast area will remain beneath
northwesterly flow aloft as an upper level ridge builds along the
West Coast. The cold air of the last few days continues to move
east as gusty westerly winds increase over the next few days along
with a warming trend back above seasonable averages. Variable
clouds aloft will prevail through the end of the week but the only
chance of any precipitation will be confined to the very highest
peaks of the Continental Divide in and around Glacier park. The
only possibility for active weather of any sort will be along the
east slopes of the Rocky Mountains where downslope winds could
approach high wind criteria through favored canyons and passes due
to tight surface pressure gradients but mid and upper level winds
do not look favorable for any type of downslope windstorm activity
at this time. Mpj

Friday night through Wednesday...period begins with weak shortwave
trof working its way through Mt, bringing widespread clouds but only
expected precipitation will be light, occasional snow showers along
the rocky mtn front and over parts of the central/southwest mtn
ranges. Our region remains under northwest flow aloft through the
weekend, then gradually shifts more westerly as broad high pressure
ridge along the Pacific coast moves into the Great Basin and
northern rockies. The portion of the ridge over Montana and southern
British Columbia/Alberta is flattened a bit on Mon/tues as a deep Gulf of Alaska
trof begins to dig south along the British Columbia coast. Forecast models, which
had been in good agreement up to this point, diverge late tues into
Wed with the GFS bringing a sharp cold front and widespread light
snow into the state, while the European model (ecmwf) keeps the low pressure system
along the West Coast, with the ridge and its dry conditions
persisting over Montana. Forecast grids lean more toward the ec solution
at this point, but do have a mention of slight chance for showers
along the hiline and rocky mtn front Wed aftn/eve. Finally, the
dominant ridge pattern will produce above normal temperatures for
most of this forecast period, with upper 40s to mid 50s for weekend
and mid-upper 50s for early next week.


updated 01741z.
High pressure is building aloft and the airmass is beginning a
lengthy period of warming and drying. A weak disturbance will move
through the flow aloft Thursday and help strengthen surface winds
across The Rockies and adjacent plains. VFR conditions will prevail
thought the next 24 hours.


Preliminary point temps/pops...
gtf 19 45 29 51 / 0 0 0 0
ctb 19 45 29 50 / 0 0 0 0
hln 17 47 29 54 / 0 0 0 0
bzn 11 43 21 51 / 0 0 0 0
wey 3 34 8 39 / 0 0 0 10
dln 14 46 25 52 / 0 0 0 0
hvr 13 46 26 53 / 0 0 0 0
lwt 15 44 28 48 / 0 0 0 0


Tfx watches/warnings/advisories...



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