Area forecast discussion
National Weather Service Grand Junction Colorado
426 am MDT Friday may 24 2013
Short term...(today through saturday)
issued at 424 am MDT Friday may 24 2013
Today...fire weather continues to be the number one concern today.
Strong SW winds at the surface and aloft will redevelop ahead of a
closed low over the pacnw. Dry conditions will continue with
humidities lowering to the single digits and low teens across the
area. The winds will not be as strong as on Thursday because no
jet speed maximum or vorticity maxima will be present to squeeze the
gradient. Still the winds should easily hit red flag criteria as
along with the low relative humidity in those zones having the needed dry fuels.
Tonight...the surface flow will decouple from the stronger upper
level flow by sunset this evening. As a result...surface winds
will diminish and become more typically downslope. Nighttime
temperatures will see just a slight warming.
Saturday...little change to the dry...warm and gusty conditions
as strong southwest flow remains continues over the forecast area
through Saturday and beyond. The Pacific northwest low will reload
with a trough extending southward along the West Coast. Also high
pressure remains entrenched over the Great Plains. The above
normal temperatures will again result in a deep mixed layer by the
afternoon allowing the strong flow aloft to mix to the surface.
Gusty winds will mix to the surface by Saturday afternoon.
Long term...(saturday night through thursday)
issued at 424 am MDT Friday may 24 2013
Saturday night-Sunday...models indicate that the wound up low
over the Pacific northwest will begin to break up a little on
Sunday. But that will not result in much of a change for our
forecast area. The elongated trough will remain over the West
Coast...and high pressure continues to dominate the Great Plains.
Therefore the strong southwest flow will continue to stream over
the area...with gusty winds again developing by early afternoon at
the surface. Temperatures will remain warm with highs 7-10 degrees
above normal...and lows closer to normal values.
Sunday through Thursday...conditions should stay dry...warmer than
normal and breezy across the area Sunday and Monday with steady SW
flow continuing. A trough off the West Coast is projected to move
inland Tuesday...causing the flow to back to the south and increase.
The GFS has the trough moving bodily over the area Wednesday and Thursday
with stronger winds and a better chance of rain.
&&
Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 424 am MDT Friday may 24 2013
VFR conditions will prevail across eastern Utah and western Colorado.
Gusty southwest winds will increase again this afternoon and early
evening causing mechanical turbulence the mountains.
&&
Fire weather...
issued at 424 am MDT Friday may 24 2013
Occasional southwest breezes will be most pronounced over the
south...and along the north sides of mountain ranges through this
morning. Then by early afternoon gusty southwest will again increase
across the area as the mixed layer deepens. The flow will not be
quite as strong as on Thursday...but gusts above 25 miles per hour will be
commonplace area-wide. Also the very dry conditions are expected to
continue. This will result in critical fire weather conditions where
fuels are dry. Therefore the red flag warning will remain in effect
for the lower elevations of Colorado zones 207 and 291.
Critical fire weather conditions are possible again on Saturday so a
Fire Weather Watch was issued for zones 291 and 207. By Sunday the
critical wind threshold of 25 miles per hour may not be as widespread so
forecast certainty diminishes somewhat. Overall though above normal
temperatures...below normal relative humidity...and gusty SW winds continue into
Memorial Day.
Next week the West Coast trough of low pressure begins to push
across the inter-mountain west. This will bring a cooling trend and
a chance of showers on Tuesday through Thursday.
&&
Gjt watches/warnings/advisories...
Colorado...red flag warning until 9 PM MDT this evening for coz207-291.
Fire Weather Watch from Saturday afternoon through Saturday
evening for coz207-291.
Utah...none.
&&
$$
Short term...cc/eh
long term...cc/eh
aviation...cirrocumulus
fire weather...cc/eh
