Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS65 KBOU 182048

Area Forecast Discussion
National Weather Service Denver/Boulder CO
248 PM MDT WED MAY 18 2016

.SHORT TERM...(This afternoon through Thursday)
Issued at 245 PM MDT Wed May 18 2016

Scattered showers and isolated t-storms have stayed over the high
terrain this afternoon due in large part to light southeast
transport winds. a moist southerly low-level flow on the plains
have kept many locations east of the I-25 urban corridor clouded
over all day. Models indicate some cape out there but also a bit
of cin to over come. So will keep showers chances below 10 percent
out there for the rest of this afternoon and early this evening...
then zero chances rest of the night. In the high country...bulk of
the t-storms/lightning strikes have remained south of I-70...but
this may change over the next few hours compliments of weak lift
and mid-level instability generated by a poorly defined shortwave
trough sweeping down from southern wyoming. Storms generated by
this disturbance likely to be of short duration and low intensity
due to their late start.

Overnight...the upper low and its bundle of moisture and weakening
large scale ascent continue to pass south of Colorado. As it moves
across New Mexico...the mean layer flow over eastern Colorado
shifts from a moist southeasterly to a drier south-southwesterly
component. This should result in gradual clearing overnight over the
plains and later over the high country. Fog not expected on
the plains tonight except perhaps in moist river bottom areas.

On thursday...upper low and attended trough shifts east-
southeast of Colorado allowing a shortwave upper ridge and
warmer/drier air aloft to spread eastward over Colorado during
the day. 700-500 mb flow becomes zonal and 700 mb temperature over
the Front Range urban corridor warm 4.0-4.5 deg c 00z/Thu-
00z/Fri. More sunshine and warming aloft should warm sfc
temperatures 8-12 deg f. High Temperatures on the plains in the
low to mid 70s back to near average for mid May. Shower and
t-storm chances lower tomorrow with scattered pops in the high
country by afternoon due in large part to strong daytime heating.
Chances on the plains less than 10 percent with a drier
environment in place.

.LONG TERM...(Thursday night through Tuesday)
Issued at 245 PM MDT Wed May 18 2016

On Friday an upper level ridge will be in place over the state
ahead of a closed low over the pacific NW. Moisture over the
mountains combined with 1500+j/kg will create enough instability
for afternoon thunderstorm development. On the plains conditions
will remain dry with the help of a lee side trough and subsequent
downsloping. Temperatures will continue to increase with highs on
Friday in the upper 70s to lower 80s.

Conditions will continue to dry as ridging moves in and drier SW
flow dominates for Saturday. Temperatures will increase with
highs in the 80s. On Sunday the upper level low weakens into an
open wave with a 90+ kt jet over western CO by Sunday night.
Increasing precipitation Sunday night into Monday with an
accompanying cold front will keep showers in the mountains until
early Monday and drop temperatures into the upper 60s. By the late
afternoon on Monday models are showing some QPF over the higher
terrain that could carry over into the Foothills overnight Monday
bringing a slight chance of showers with overnight temperatures
into the 40s. Strong UL SW flow will continue on Tuesday with a
slight chance of convection in the mountains and highs in the
upper 60s to lower 70s.


.AVIATION...(For the 00Z/Thursday TAFS through 00Z/Friday
TAFS) Issued at 245 PM MDT Wed May 18 2016

Scattered-broken 4000-5000 foot cigs expected to remain over the
Denver area through late this evening. Then clearing. Fog not
anticipated tonight with the presence of a drier downslope/
southerly flow. There still a low chance that the metro area could
see rain shower and/or t-storm until 02z this evening. Gusty
erratic winds...a brief light rain shower and perhaps a few cg
lightning strikes all that are expected. Then gradual clearing
after midnight. On Thursday...VFR conditions on tap with light
south-southwesterly winds all day. Any shower activity should
remain confined to the elevated terrain south and west of Denver
during the afternoon hours.


.BOU Watches/Warnings/Advisories...


AVIATION...Baker is the U.S. government's official web portal to all federal, state and local government web resources and services.