Red Flag Warning 30, NWS Denver/Boulder, CO

989 
WWUS85 KBOU 160148
RFWBOU

URGENT - FIRE WEATHER MESSAGE
National Weather Service Denver/Boulder CO
748 PM MDT Fri Jun 15 2018

COZ211-213-160300-
/O.CAN.KBOU.FW.W.0030.000000T0000Z-180616T0200Z/
Jackson County Below 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
748 PM MDT Fri Jun 15 2018

...RED FLAG WARNING IS CANCELLED FOR WIND AND LOW RELATIVE
HUMIDITY FOR NORTH PARK AND MIDDLE PARK...

The National Weather Service in Denver has cancelled the Red Flag
Warning.

Temperatures have cooled down this evening and humidity levels 
have increased. Fire danger levels have relaxed, and the threat of
dangerous fire behavior no longer exists. Shower and thunderstorm
activity is expected to increase over the next few days which will
also lead to cooler temperatures. 

$$

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1023 AM MDT Fri Jun 15 2018

.UPDATE...
Issued at 952 AM MDT Fri Jun 15 2018

Overall, no significant changes to the forecast. Add gusty winds
to the grids with thunderstorms this afternoon and evening. There
is a slight increase in precipitable water values, but
inverted-v profile would support strong winds with limited
rainfall, especially from the urban corridor westward to the
foothills.

&&

.SHORT TERM...(Today and tonight)
Issued at 340 AM MDT Fri Jun 15 2018

Broad high pressure aloft over southern plains states while upper
trof making some progress through the Pacific northwest states.
The result is a light to moderate southwest flow aloft over
Colorado. Still some varying amounts of mid/high level moisture
over Colorado but levels are fairly similar to yesterday morning
at this time. There will be a weak cold front moving southward
across northeast Colorado this morning, and right now has just
passed CYS and into northern sections of Larimer and Weld
counties. Low level moisture is higher behind this front with
dewpoints in the lower 50s. So the surface will cool a few degrees
behind the front today but 700mb temps are still rather close to
yesterday at 17c. Afternoon high temperatures will be in the lower
to mid 90s over the plains this afternoon, again a bit cooler
than yesterday due to the front and perhaps a bit more afternoon
cloud cover.

Forecast soundings for this afternoon still are the inverted-v
types with continued dry low levels. Main threat again will be
gusty winds with the showers, especially mountains and front
range/adjacent plains. Further east on the far northeast plains,
storms should be a bit stronger with higher dewpoints with
potential CAPE values upwards of 2000j/kg. Could be an isolated
severe storm with damaging winds to 60 mph and hail up to 1 inch
in diameter. Showers and storms expected to move out of the
area/diminish by midnight tonight.

.LONG TERM...(Saturday through Thursday)
Issued at 340 AM MDT Fri Jun 15 2018

The abnormally moist large scale ridge-trough circulation pattern
over the western and central CONUS during the next several days
according to the GFS/NAEFS, ECMWF, UKMET and Canadian GEM,
promises to generate ample cloud cover, cooler temperatures, and
periods of moderate to heavy precip for the forecast area. Air
laden with subtropical moisture streaming up from the Gulf of
Mexico is progged to merge with an equally moist north bound
atmospheric river along the west coast of Mexico at the present
time. Embedded within the western moisture stream will be remnants
of Tropical Storm Bud. Next, a deep, unseasonably cold upper
trough propagating south over California and Nevada early in the
period causes a closed mid-level cyclone off the srn California
coast to drive inland over nrn Baja where it merges with the remains
of Tropical Storm Bud. NAM and GFS show these features combining
into an open wave and lifting newrd over Arizona/wrn New Mexico
Sat/Sat night, and eventually over Colorado Sun/Sun night.
At the core of the Mexican atmospheric river, mean layer
precipitable water values range from 2-3.5 standard deviations
above average. All this moisture is projected to reach srn
Colorado by Sat afternoon, and n-central/nern Colorado by late Sat
night/Sun morning. Meanwhile, a cold front is forecast to slip
south acrs nern Colorado during the pre-dawn hours Sun, with a sfc
low forming on this bndry up near Sterling. Circulation around
this low will likely enhance the northeast/upslope flow behind the
front, consequently piling low- level moisture up against the
Front Range and Palmer Divide. Models indicate afternoon PW values
along the Front Range over 1.25 inches. QG omega fields also
indicate an increase in large scale lift through the day in
advance of the shortwave approaching from the 4-corners area.
Either late afternoon or early evening, could see a line of shwrs/
t-storms slowly moving off the Front Range and over the I-25
corridor, possibly producing 1-2 inch per hour rainfall rates that
could result in localized low-land and street flooding. Burn
scars will be most prone to flooding should the heavy precip
develop. The high country should also see periods of moderate to
heavy precip Sat night and Sun. The heaviest precip in the high
country Sun may fall roughly north of I-70 during max heating and
with the passing shortwave. Steep lapse rates could also generate
a few late day storms capable of hail.

Sun night, models show the subtropical moisture plume shifting north
and east of the forecast area, and therefore a drop off in precip
along with partial clearing. The lull in precip appears short-lived
with the cold upper trough out west migrating east, and yet another
cold front dropping in from Wyoming. The approaching trough cools
and re-saturates mid and high-levels, while post-frontal upslope
flow cools temperatures even further and returns low-level moisture
to the high plains. Could see another round of locally heavy
rainfall over and along the Front Range Mon afternoon and evening.

Mon through Thu, weather conditions should remain moist and
unsettled across the region with waves of moisture flowing up into
Colorado around a broad, unusually cool upper trough hanging out
over the northwest quadrant of the CONUS. Showers and t-storms
will remain in the forecast every day, with the best chance for
measurable precip over and adjacent to the Front Range during the
afternoon and evening hours. Temps through the period are likely
to stay below average for mid June with the coolest readings Mon
and Tue. Warming late in the period should result in more
thunderstorms and less showery type precip.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 952 AM MDT Fri Jun 15 2018

East/northeast surface winds expected following the weak cold
front earlier this morning. Could see a bit higher threat of
showers/storms this afternoon given the higher low level moisture
behind the am front. Still main threat will be gusty and erratic
winds. Current TAF has this covered so only minimal changes
planned for 18z issuance.

&&

.FIRE WEATHER...
Issued at 952 AM MDT Fri Jun 15 2018

There will still be elevated fire concerns over the high mountain
parks this afternoon. Expect a bit less winds and slightly higher
humidity levels so will not issue any Red Flag warnings today with
marginal conditions. Gusty and erratic winds in the 35-45 mph
range with some of the thunderstorms as well.

&&

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

UPDATE...Cooper
SHORT TERM...Entrekin
LONG TERM...Baker
AVIATION...Cooper
FIRE WEATHER...Entrekin/Cooper

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1127 AM MDT Fri Jun 15 2018

COZ030>051-161730-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
1127 AM MDT Fri Jun 15 2018

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

Expect isolated to scattered coverage of afternoon and evening
showers and thunderstorms over the mountains and plains. The main
threat with the showers will again be gusty winds up to 45 mph.
Slightly cooler temperatures can be expected following the
passage of a weak cold front earlier this morning, along with
higher low level moisture. This may lead to stronger and possibly
a severe storm over the far northeast plains with damaging winds
to 60 mph and hail up to one inch in diameter. The thunderstorms
will diminish by later this evening.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Shower and thunderstorm coverage will increase this weekend and
remain elevated through most of next week. The main threat from
storms this weekend will be heavy rainfall, which could result in
localized flooding. Burn scars will be particularly prone,
although urban or poor drainage areas may also see some flooding
should heavy rainfall develop.

Moist upslope flow behind a cold front will expand the risk of
heavy rainfall into the I-25 Corridor and adjacent plains Sunday
afternoon and evening. One or two storms may also be severe with
large hail the main threat. The unsettled weather and potential
for locally heavy rainfall will remain in the forecast through the
mid part of next week. A couple severe storms will again be
possible Tuesday and Wednesday afternoon and evening.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.