782
FXUS65 KBOU 092350
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
550 PM MDT Tue Jul 9 2024

.KEY MESSAGES...

- Mostly dry with continued warming throughout the week.

- A heat wave is expected Friday through Monday with temperatures
  reaching 98 to 104 degrees across the urban corridor and
  plains. Heat related highlights will likely be needed during
  this stretch.

&&

.SHORT TERM /Through Wednesday/...
Issued at 249 PM MDT Tue Jul 9 2024

Radar currently shows scattered showers and weak thunderstorms
across the mountains, foothills, and southern Lincoln County this
afternoon. Marginal instability and mid-level moisture will be
sufficient to support continues showers and a few weaker storms
through early this evening. An ACARS sounding taken from near
Denver displays a clear inverted v profile, indicative of a dry
surface layer. This environment may support a stray shower or two
making it onto the adjacent plains; however, more likely high-
based/virga with a brief gust up to 30 mph. Otherwise the higher
chances will be confined to the higher terrain.

Wednesday the upper level ridge slowly slides a bit more eastward
over the region. 700mb temperatures warm a degree or two
supporting highs in the low 90s across the plains and urban
corridor. The high country will see highs in the 70s for the
foothills/valleys and 50s/60s for the mountains. Similar to
Tuesday, marginal instability develops in the high country in the
afternoon to support terrain forced showers/storms. Limited
moisture will likely keep coverage scattered.

&&

.LONG TERM /Wednesday night through Tuesday/...
Issued at 249 PM MDT Tue Jul 9 2024

Upper level high over the Great Basin will bring a northerly flow
aloft to Colorado for Thursday. Temperatures increase as the high
nears Colorado with high temperatures climbing into the mid to
upper 90s over northeast Colorado. Expect another round of
isolated/scattered weak showers and storms over the higher
terrain. With northerly flow, these showers/storms will drift
southward across the higher terrain and not onto the near plains.

Full brunt of the upper level high to be felt Friday through
Monday with highs climbing into the 98F to 104F range across the
Urban Corridor and eastern plains. The high very slowly moves east
across the Central and Southern Rockies this weekend and Monday.
Very little change in temperatures is expected during this period.
Models are showing 700mb temperatures reaching 19-22C each day
Friday through Monday. Sounding climatology shows 21.0C and warmer
at 700mb has only been reached 15 times and 22.0C has only been
topped 4 times. Thus, we expect some daily high temperature
records to fall. Speaking of which, these are the records highs
for DEN...101F (Fri), 100F (Sat), 100 (Sun), and 101 (Mon).

As far as precipitation goes Friday through Monday, a few weak
showers and thunderstorms will be possible over the higher terrain
each day. With precipitable water values staying below normal and
CAPE less than 500 J/kg each day, the showers and storms should
only produce brief light to moderate rain, but with gusty outflow
winds. May see a slight increase in showers and storms Sunday and
Monday as moisture slowly increases. Weak steering winds are
expected to keeping any convective activity and most of the clouds
over the higher terrain.

Models show the center of the ridge shifts east of Colorado
Tuesday. The southerly flow aloft increases subtropical moisture
over the area, which will result in better chances for
showers/thunderstorms and slightly cooler temperatures. However,
this high has been slow to arrive and it may be slow to leave,
which would mean the heat could linger into Tuesday. Will start to
trend temperatures slightly cooler and have better chances for
showers/storms on Tuesday.

&&

.AVIATION /00Z TAFS through 00Z Thursday/...
Issued at 537 PM MDT Tue Jul 9 2024

VFR through the TAF period. Fairly strong outflow boundary moving
across the terminals through 01z, with BJC already recording a
couple gusts near 30kt. Gusty winds will likely continue for an
hour or so before weakening, and then should transition to light
drainage flow later this evening. Light east/northeast flow is
forecast for tomorrow afternoon. With a little less convection
expected across the high country, chances of any outflow
boundaries is lower than today.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...Mensch
LONG TERM...Meier
AVIATION...Hiris