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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
432 am MDT Sat Mar 28 2015

Short term...(today through tonight )
issued at 431 am MDT Sat Mar 28 2015

Drier and slightly warmer air over our area today. Expect surface
winds to stay westerly with mixing of westerlies aloft
overwhelming the southerly surface tendency as pressure falls
develop north of US. With the drier air humidities will be lower
today...increasing the fire danger. Most areas will not have
enough wind for a warning...but near the Wyoming border it will be
windier. A red flag warning will be issued for eastern Larimer and
northern Weld counties for this afternoon where conditions will be
worst. These areas also missed out on the rain a few nights ago.
For the foothills...strongest winds will also be near the Wyoming
border...less wind in most areas...cooler temperatures and better
fuel moisture so no warning there though the Livermore area will
have similar conditions to the plains areas in the warning.

Shortwave moves across the northern rockies tonight dropping a
cold front across Colorado. Not much beyond a wind shift and the
cooling...I did hold on to very low probability of precipitation for the northern
mountains and northeast corner this evening with the frontal is more likely that there will be nothing. Cooled
tonights lows a little as the models are showing about 15 degrees
of cooling with the front...and temperatures in the northern High Plains
are in the 30s to lower 40s.

Long term...(sunday through friday)
issued at 431 am MDT Sat Mar 28 2015

On will be fairly quiet with a weak west to
northwesterly flow aloft...and little in the way of a surface
pressure gradient to drive the wind. The models do indicate some
minimal quantitative precipitation forecast in zones 34 and 37 in the afternoon. The nam12 soundings
show some instability in the afternoon...maybe enough to produce a shower or
thunderstorm so will go with isolated coverage there...otherwise dry. The ridge
of high pressure will build over the western U.S. On Monday with
the flow aloft a bit stronger. In addition...a Lee side trough
develops over eastern Colorado. Best chance of any showers will be in the
mountains...with downslope negating the shower potential over the
northeast plains. Temperatures will again moderate to well above
seasonal normals...middle 70s. The upper ridge axis shifts eastward
over Colorado by Tuesday. Overall...continued very warm and dry
with just some isolated shower potential in the high country Tuesday
afternoon and Tuesday night. Late Tuesday night into Wednesday...
a stronger west-southwesterly flow will be over Colorado as a
system brushes across northern Colorado. A decent surface pressure
gradient as well. It will be cooler with the passage of a cold
front...but temperatures will still be above normal. Limited
moisture will remain mainly north of the County Warning Area so mainly dry and windy
with some high based showers associated with the passage of the
front on Wednesday. A strong zonal flow aloft will be over
Colorado on Thursday...with another system prognosticated to drop out of
the northwest and into the region Thursday night into Friday
morning. Best chance of showers will be from the Front Range
foothills eastward. Cooler as well with temperatures closer to
normal on Friday. Both the GFS and European model (ecmwf) show a trough moving over
the area at that time...with the European model (ecmwf) generating a little more
quantitative precipitation forecast over northeast Colorado on Friday.


Aviation...(for the tafs through 12z Sunday morning)
issued at 431 am MDT Sat Mar 28 2015

VFR through tonight. West winds will continue today but speeds are
expected to remain below 20 knots at kden/kapa. Gusts into the 20s
are possible at kbjc for a few hours this afternoon.


Bou watches/warnings/advisories...
red flag warning fire zones 238 and 242 from noon until 6 PM MDT.



Short term...gimmestad
long term...Cooper

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