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FXUS65 KBOU 170934

Area Forecast Discussion
National Weather Service Denver/Boulder CO
334 AM MDT Sat Aug 17 2019

.SHORT TERM...(Today and tonight)
Issued at 333 AM MDT Sat Aug 17 2019

On Saturday, a broad upper level trough of low pressure will
stretch from the Pacific Northwest across the Northern Rockies 
and into the Northern Great Plains States. Colorado will lie on 
the southern end of the trough under the the influence of a 
moderate westerly flow aloft. This pattern will bring mostly dry 
weather and above normal temperatures to north central and 
northeastern Colorado. There should be enough surface moisture 
combined with a passing shortwave to produce a few late afternoon 
and evening storms across the far eastern sections of the CWA. 
Instability should be somewhat limited; therefore, any storms that
do develop should only produce brief light to moderate rainfall 
and gusty winds. Temperatures are expected to be around 5 degrees 
above normal across the Front Range Urban Corridor and adjacent 
plains with highs in the lower 90s. Slightly cooler air will 
linger across the far northeastern corner of the state with highs 
in the mid to upper 80s. 

Saturday night will be dry with the exception of a few lingering
showers or storms near the Kansas and Nebraska border during the
evening. Many of the models are showing a surface high pressure
center dropping southeast across the northern Great Plains
overnight. A surge of cool moist air associated with this center
is progged to push into northeastern Colorado early Sunday
morning. If this verifies, we could see some low clouds develop
over the plains, mainly east of Denver by sunrise.

.LONG TERM...(Sunday through Friday)
Issued at 333 AM MDT Sat Aug 17 2019

Overall pattern for Sun and Mon will be dry as flow aloft 
transitions from westerly to southwesterly by Mon. As far as 
temperatures, there is a weak front that moves into nern CO early
on Sun. There is some disagreement as to how this feature may 
affect highs across the plains. For now, will have highs ranging 
from the mid 80s, over the far nern plains, with lower 90s along 
the front range. On Mon with southwest low level flow in place, 
highs will warm into the mid to upper 90s over nern CO.

By Tue an upper level high will be over the area with weak flow 
aloft.  A cold front is fcst to be near the WY-NE border by 18z and 
then move across nern CO thru the aftn hours.  There is some 
disagreement as to where convection will develop with this front. 
The ECMWF keeps most of the convection over the far nern plains 
while the GFS shows the best chance closer to the foothills Tue 
evening.  As for highs, based on current timing of the front, 
readings will be in the lower to mid 90s over nern CO.

For Wed, weak northwest flow aloft will be over the area as the 
upper level high will be near the four corners area.  Overall there 
will be some subtropical moisture moving into the area, so should
see a better chance of storms over the higher terrain. Across 
nern CO deeper low level moisture will be in place with southeast 
low level flow. Thus will keep in a good chance of storms. Highs 
on Wed will be cooler across the plains as readings drop back into
the upper 70s to mid 80s.

By Thu, the upper level high will move west into the Great Basin 
with north to northwest flow aloft.  Cross-sections still show 
enough moisture top keep in a chance of storms over the higher 
terrain.  Over nern CO, will keep in a chance of storms mainly along 
the front range. As for highs, readings will be near seasonal 


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 333 AM MDT Sat Aug 17 2019

Southerly drainage winds are expected through mid morning becoming
northwesterly by afternoon. Dry weather is expected through the
period. However, can't rule out an isolated high based shower or 
late day storm. 


Issued at 333 AM MDT Sat Aug 17 2019

Fire danger will continue to be elevated in the mountains and 
over the higher foothills Saturday afternoon due to low relative 
humidity and gusty westerly winds up to 25 mph. Be sure to adhere 
to local fire bans.

Elevated fire danger will continue both Sunday and Monday
afternoon's due to above normal temperatures and low humidity 
readings. Winds will be generally light except over the northern




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