Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 191132

Area Forecast Discussion
National Weather Service Denver/Boulder CO
432 AM MST Sat Jan 19 2019

.SHORT TERM...(Today and tonight)
Issued at 304 AM MST Sat Jan 19 2019

NW flow aloft will be over the area today thru tonight.  Cross-
sections show a shallow layer of moisture will affect the mtns today
and tonight.  Although orographic component is favorable lapse rates
are fairly stable so any snow that does occur will be very light.
Cross-sections show a mtn wave will be in place, however, component
along winds are only in the 30-35 kt range so speeds will stay below
highlight criteria across the higher terrain and at lower elevations
near the WY-CO border.  As far as highs, readings should reach the
upper 40s to lower 50s across the plains.

.LONG TERM...(Sunday through Friday)
Issued at 425 AM MST Sat Jan 19 2019

Models give us upper ridging Sunday and Sunday evening. Strong
upper level southwesterly flow is in place the rest of Sunday
night and much of Monday. By late Monday the next upper trough
moves into and through Colorado by Tuesday morning. The QG Omega
fields show gradually increasing upward vertical velocity for the
CWA Sunday afternoon through Monday evening. The upward energy is
pretty strong over the CWA Monday afternoon and early evening. The
upward energy is in place all of Monday night into Tuesday
morning. The low level winds seem to dominated by downsloping on
the models Sunday well into Monday. By late Monday and Monday
evening, a pretty decent cold front and upslope is progged into
the CWA. For moisture, there isn`t much in the lower and middle
levels Sunday into Monday morning. Moisture increases from west
to east late Monday morning through the afternoon. Pretty deep
moisture is in place later Monday afternoon into Tuesday morning
for all areas. The QPF fields show tiny amounts of measurable
snow over the northwestern CWA mountains Sunday morning. The QPF
fields bring in the measurable snowfall with the next trough from
Monday afternoon 18Z and onward into Tuesday morning. The NAM has
the moisture snowfall with the storm by 12Z Tuesday morning. All
the models show some measurable snow for all the plains. Will go
with "likely"s for most of the CWA, especially for the Monday
night period. For temperatures, Sunday`s highs will be 1-4 C
warmer than today`s. Monday`s looks to be similar to Sunday`s
highs. For the later days, Tuesday through Friday, models have
northerly flow aloft on Tuesday. Models have a large mean trough
over the eastern three-quarters of North America Wednesday well
into next weekend. The CWA is open to the cold air and there will
be northerly and northwesterly flow aloft all four days. There is
minor measurable snowfall on the QPF fields over much of the CWA
Wednesday afternoon through Friday here and there. Nothing


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 304 AM MST Sat Jan 19 2019

VFR conditions today thru tonight.  Winds were southeast early this
morning and should remain in that general direction thru midday. By
early aftn they will become west or northwest and then become
southwest by early evening. By midnight they will become drainage.




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