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Area forecast discussion
National Weather Service Grand Junction Colorado
314 PM MDT sun Apr 30 2017

Short term...(tonight through Monday night)
issued at 314 PM MDT sun Apr 30 2017

Region will remain in cool northwesterly flow the next couple of
days as troughiness encompasses the eastern 2/3rds of the US and
weak ridging builds over the eastern Pacific Ocean. A weak
disturbance over Idaho early this afternoon is making its way into
northern Utah and will bring mid and high level clouds to the
region tonight. Despite the northwest flow, warm air advection is making its way
into the region already seen at the surface by comparisons with
temps 24 hours ago today. Many locations as of 3pm are showing
temps about 10 degrees warmer than yesterday, with forecast
guidance for low temps tonight indicating temps 10 degrees warmer
in many spots than last night thanks to the expected cloud cover.
Snow and rain/snow mix showers are expected over The
Gore/Flattop/Elkhead/park ranges tonight and possibly an isolated
shower over the San Juans and Maroon Bells wilderness area too.
These showers are expected to persist through the mid morning
hours and could cause some slick roads across these regions. Some
clearing is expected Monday afternoon before another disturbance
moves in on Tuesday.

Long term...(tuesday through sunday)
issued at 314 PM MDT sun Apr 30 2017

Thicker cloud cover and wider coverage of showers and
thunderstorms are expected to develop on Tuesday as another vort
Max in northwest flow arrives across the region. Building cumulus will be
common in the afternoon, but there are some differences in
forecast models on the extent of shower coverage. Since we are in
early may, expect rain and a rain/snow mix if traveling in the
mountain terrain, with a lightning threat as well on the high

Clearing is expected from Wednesday on as high pressure
builds in from the west. High pressure axis will reach Utah and
Colorado sometime late Thursday into Friday which will increase
temperatures across the region to near 10 degrees above normal. By
Saturday the long range models are indicating the next trough
moving onshore the Pacific northwest which will help to increase winds
and available moisture across the region over the weekend. Low
confidence on model solutions from next weekend on, but general
pattern suggests that temperatures may remain near or above normal
with showery afternoon heating- induced activity beginning next


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1102 am MDT sun Apr 30 2017

VFR conditions will prevail at all taf sites through about 03z
this evening. Thereafter a weak trough will bring clouds and
scattered to numerous showers to the Colorado northern and west-central
mountains near the Continental Divide, occasionally obscuring the
mountains. Occasional rain then snow showers will be in the
vicinity of kege and kase along with cigs below ils breakpoints.


Gjt watches/warnings/advisories...

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