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National Weather Service Grand Junction Colorado
432 am MDT Wednesday Jul 30 2014

Short term...(today through thursday)
issued at 432 am MDT Wednesday Jul 30 2014

A few showers persisted over the Steamboat Springs area...The Flat
Tops...and in the vicinity of Eagle early this morning. Elsewhere
..the weather was quiet. A weak upper low over southwest Wyoming
was poised to begin moving across the north this morning and will
continue to move to the southeast this afternoon. Lift associated
with this feature will mainly affect the north today with showers
redeveloping this morning. Model forecasts of precipitable water
Don/T show much change and dewpoints remain elevated this morning.
Forecast model cape and lifted indices not very impressive due to
relatively cool conditions. Consequently...expect a little bit of
a downturn in activity but not much. Storms will continue to
produce moderate to heavy rain which cause problems for some
areas. not expect convection to be as widespread and
organized as yesterday so will not be hoisting a Flash Flood Watch

We should see showers and thunderstorms diminish in a more timely
fashion this evening as any lingering energy shifts away to the
east by late in the day. However we do not see much of a drop in
dewpoints through a few showers may persist
overnight. Moisture drops just a notch on Thursday. But with no forcing
mechanism beyond the diurnal and differential heating...expect
showers and thunderstorms will be more confined to the higher
terrain...and will not be as heavy as the last couple of days. The
better drying will be in the north. Temperatures will increase a
few degrees but will still remain below normal values.

Long term...(thursday night through tuesday)
issued at 432 am MDT Wednesday Jul 30 2014

Another upper wave will rotate across the forecast area on Friday.
This wave will not be near as strong as yesterday/S disturbance
.. but will result in an uptick in showers and thunderstorms
over Thursday/S activity. Models have indicated that the upper
vorticity center will reach northeast Utah around sunrise then be over
the northern two thirds of the County Warning Area by midday. Therefore...showers
and thunderstorms will begin earlier than in the typical diurnal
pattern. Expect a few storms could be strong with heavy rain...but
do not expect a repeat of Tuesday as the ingredients are not all
coming together as well. Moisture remains lower with precipitable
water values ranging from around 0.6 inch up to an inch from north
to south. Also the strength of this upper impulse is not near as
impressive. Again expect a couple degrees of warming...mainly
north. But still most locations will not reach normal values.

Saturday a bit drier as high pressure becomes centered over The
Four Corners. Diurnal thunderstorms will still form but coverage
and intensity will be reduced as moisture levels sink further.
Pattern begins to shift Sunday as low pressure off the West Coast
moves over the Desert Southwest during the day forcing high
pressure east and allowing moist subtropical air to again sweep
northward. Showers and thunderstorms still favor the mountains but
coverage will be more widespread across the south. Details differ
between the GFS and ec with respect to the low/S movement to the
northeast. However...both show the surge of subtropical air over
the region through the middle of the week will persist raising
the threat of heavy rain. As moisture increases...temperatures
will cool from near normal to several degrees below.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 432 am MDT Wednesday Jul 30 2014

A handful of areas of light to moderate rainfall lingered over
the northern and central mountains early this morning...otherwise
the weather was quiet across the forecast area. MVFR ceilings are
likely to linger in the lower elevations east of a kdwx to kcag
line through 14z while VFR conditions expected to persist

Remnants of yesterday/S disturbance will move slowly across
northeast Utah and northwest Colorado this morning which will
yield scattered showers and isolated thunderstorms from middle to
late morning. Gobs of residual moisture lay across eastern Utah
and western Colorado which will again fuel showers and
thunderstorms after 18z through 03z/Thursday across the entire region
with mountains favored. Therefore...expect broad areas of mountain
obscuration and gusty outflow winds to 30 to 40 miles per hour in the
vicinity of thunderstorms. Taf sites in northeast Utah and along
the I-70 corridor east of kril will likely experience moderate to
heavy rain showers and/or thunderstorms this afternoon. Storms
will likely briefly lower visibility to IFR with MVFR ceilings possible.
Chances for taf sites to the south and west are greatly reduced.

Some showers and a few thunderstorms may linger along The Divide
mountains after 09z but VFR conditions are expected to prevail


Gjt watches/warnings/advisories...




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