National Weather Service Raw Text Product

185 
FXUS65 KBOU 181134
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
534 AM MDT Mon Jul 18 2022

.SHORT TERM...(Today and tonight)
Issued at 318 AM MDT Mon Jul 18 2022

The main story today will be the heat and record setting high 
temperatures expected across eastern Colorado. Today will be the 
hottest day of the week as thermal ridge shifts over Colorado with
700mb temperatures climbing between 20c-21c. This a 2 degree C 
increase over yesterday which will equate to about 3-5 degrees 
warming from Sunday's readings. The Denver record today is 99 
degrees and this expected to be broken with highs at Denver around
101. A heat advisory has already been issued for much of 
Northeast Colorado from later this morning through the evening. 
The only fly in the ointment is impact of increasing cloud cover 
this afternoon, where clouds could impact temperatures a few 
degrees pending on cloud arrival. 

Water vapor showing moisture already on the upswing over western 
Colorado with ongoing showers and a few storms across southwest 
Colorado and eastern Utah. The upper high will be sliding southward 
into Northern New Mexico later today in response upper trof moving 
across the northern Rockies and northern high plains. The mid level 
flow will in turn be shifting more westerly and increasing this 
afternoon. This increase in moisture will result in an increasing 
chance of showers and thunderstorms over the mountains and higher 
terrain this afternoon. Precipitable water values will be 
increasing to close to an inch over the Front Range and plains
with .7 to .9 over the mountains. Forecast soundings becoming 
inverted-v profile with mainly mid level moisture above 500mb and 
dry low levels. Impacts will be mainly gusty winds with the 
showers across the plains with DCAPE values close to 1500j/kg. 
There may be enough flow to steer isolated showers across much of 
the plains towards the evening hours and will carry at least 
isolated pops across lower elevations. 

.LONG TERM...(Tuesday through Sunday)
Issued at 318 AM MDT Mon Jul 18 2022

A strong shortwave trough will move from Montana towards 
Minnesota on Tuesday which will push the ridge over the Four 
Corners region to the south a little bit. At the surface, a cold 
front will move across our forecast during the morning. It doesn't
feel right calling this feature a cold front because there's not 
much "cold" associated with it. This front will have moderate 
northwesterly winds behind it with drier air. Even though high 
temperatures will be cooler than Monday as a result of this front,
the morning could be very warm in a relative sense. Warm 
temperatures aloft could mix down quickly with the moderate
boundary layer winds and Denver could reach 90 shortly after 9 
AM. With cooler 700 mb temperatures behind the front, temperatures
may not increase very much during the afternoon but highs will 
still be in the mid to upper 90s across the plains. Other than the
warm temperatures, there will be two weather concerns on Tuesday.
One will be fire weather as the increased winds along with dry 
conditions behind the front will lead to elevated to near critical
conditions across the plains to the north and east of DIA. The 
other concern will be gusty winds from showers and storms that 
form mainly over the higher terrain to the south of I-70 and along
the Palmer Ridge. Some gusts could reach 55 mph in the stronger
storms due to steep low level lapse rates. The threat for burn 
area flash flooding looks quite low as areas to the north of I-70 
will be rather stable which will limit storm activity. 

700 mb temperatures will decrease slightly on Wednesday as a
surface high pressure center moves from the panhandle of Nebraska
towards Kansas. Light easterly, upslope winds will develop across
the plains but the moisture return will be low. The best low 
level convergence will setup over the Palmer Divide and southern 
foothills which will lead to the best storm coverage in that area.
The plains to the north and east of Denver will again be rather 
stable and showers and storms will be very minimal there. 
Wednesday will be one of the cooler days of the week but that's 
not saying much. Highs will still be in the low to mid 90s across 
the plains.

The upper level ridge will shift slightly eastward on Thursday
with low to mid level temperatures increasing slightly. Highs 
will warm a couple degrees as a result and shower and storm 
activity will be mostly confined to the higher terrain. 

Friday looks to be another very hot day with a chance of Denver
reaching 100 degrees again. The upper level ridge will move more
directly overhead and compressional warming will increase ahead of
a trough over the Pacific Northwest. 700 mb temperatures will
likely reach 20 C and if conditions end up being sunnier than
currently expected, the record high of 102 in Denver could be
within reach. However, there is just enough mid level moisture
that moves over our forecast area that showers and storms will
limit the heating a bit in the afternoon. These storms could
produce very gusty winds due to inverted-V soundings. 

Saturday is the day where forecast guidance really starts to
diverge. Some models have a cold front pushing through the plains
with more storm activity and cooler temperatures. Other models
have Sunday being the hottest day of the week with temperatures
well into the 100s across the plains as compressional heating
ahead of a shortwave trough increases. It's too early to have much
confidence in either solution so the NBM forecast was left mostly
unchanged. 

There's a better chance that Sunday will be cooler with a cold
front having moved through the area at some point Saturday or
Sunday morning. Ensembles are hinting that a healthy wave of
monsoonal moisture may arrive during this period which could lead
to burn area flash flooding. 

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 526 AM MDT Mon Jul 18 2022

Southerly winds will decrease and shift a bit more southwest to
west through the mid morning hours then becoming west to 
northwest by late morning. Increasing moisture will lead to 
isolated high based showers from 21z-01z with main impacts of 
gusty winds up to 35kt. 

&&

.FIRE WEATHER...
Issued at 318 AM MDT Mon Jul 18 2022

Elevated fire danger across the plains this afternoon with hot
temperatures, low humidities in the 12-17 percent range and breezy
conditions. Wind speeds with areal extent and strength are 
marginal for red flag conditions so no warnings will be issued. 

Tuesday through Saturday will have minimum relative humidities in
the low teens due to the hot and dry conditions. The only day 
where the winds will be strong enough to increase the fire danger 
will be Tuesday. Winds could gust up to 30 mph behind a cold 
front across the plains to the north and east of DIA. This will 
lead to elevated to possibly critical fire weather conditions. We 
will attempt to get updated fuel moisture data during the day 
today to see if the fuels would meet the red flag criteria. A Red 
Flag Warning is possible on Tuesday. 

&&

.HYDROLOGY...
Issued at 318 AM MDT Mon Jul 18 2022

There will be an increase in moisture over the mountains today
with a resultant limited risk for flash flooding over the burn
scars. Storm motions will be quick enough to keep flood risk more
marginal. 

Conditions will be rather stable and dry on Tuesday so the burn
area flash flood threat is very low. A storm or two can't be
completely ruled out over the burn areas so the threat is still 
limited. The chance for flash flooding increases a tad on 
Wednesday as storm coverage increases slightly. The slow moving 
nature of the storms could pose a threat that day. The flash flood
threat will be low Thursday and Friday but not zero as drier and 
warmer air moves in. A healthy amount of monsoonal moisture may 
arrive by late this weekend into the following work week which 
could increase the risk of flash flooding. 

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 10 AM this morning to 9 PM MDT this evening 
for COZ038>040-042>051.

&&

$$

SHORT TERM...Entrekin
LONG TERM...Danielson
AVIATION...Entrekin
FIRE WEATHER...Entrekin/Danielson
HYDROLOGY...Entrekin/Danielson