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Area forecast discussion 
National Weather Service Pueblo Colorado
319 PM MDT Monday Jul 6 2015

Short term...(this evening through tuesday)
issued at 244 PM MDT Monday Jul 6 2015

..locally heavy rainfall with marginal strong to severe
thunderstorm threat over the mountains the next couple days...

Front has pushed through all of southeast Colorado with boundary
well to the south...across the Texas Panhandle and east central nm as
of 19z. Widespread stratus has developed behind the front across
much of southeast Colorado...with stable conditions across northern
portions of the southeast plains. Latest Storm Prediction Center mesoscale analysis shows
around 1000 j/kg of cape across the southeast mts...and adjacent I-
25 corridor...particularly along/south of Highway 50. A little less
cape across Chaffee/lake counties where dew points managed to drop
into the 40s. So appears best threat for strong to marginally
severe thunderstorms will be across the southeast mountains and San
Luis valley where convective available potential energy are greatest. Locally heavy rainfall threat
will exist for all storms today...though northern Teller and El Paso
counties look the most stable...which should cut back precipitation
rates to less than 1/2 inch per hour....keeping threat for localized
flash flooding less of a concern up that way. However...for
southern areas...wets/sangres...where easterly upslope flow
continues to push 50 dew points up the lower slopes...expect fairly
widespread showers and thunderstorms through the late evening.
Concerns for localized flash flooding is highest for these
areas...mainly for burn scars. So East Peak...Royal Gorge to name a
couple will need to be watched closely through the evening. Given
the lack of cape and a well defined shortwave...though there does
appear to be weak features embedded within the flow...have decided
not to go with a Flash Flood Watch at this point. Storms thus far
seem to lack strength and event seems to be trending more towards a
stratiform event...especially as the late afternoon and evening

Differences in the models exist as to how persistent shower and
thunderstorm activity will be over the mountains tonight. High res
models wane off the precipitation after 06z...but keep at least
scattered showers going through the overnight hours. With upslope
flow hard to argue with this scenario...though suspect that nam12
and GFS are overdone with quantitative precipitation forecast through the overnight and early
morning hours. Either way...not expecting precipitation rates to be
all that intense after 06z. On Tuesday...similar conditions will be
in place...though appears to be a better defined shortwave moving
across the area. Dew points in the 50s will remain pinned up along
the eastern slopes of the mountains in east to southeast upslope
flow...which should yield convective available potential energy of 500-1000 j/kg. Shear looks to be
on the weak side think main threat will be locally heavy
rainfall. If we can get a few sun breaks...then an isolated
stronger cell will be possible which could produce some hail up to
near quarter size. Will have to see how much rain falls this
afternoon and tonight...but its possible we will need a Flash Flood
Watch tomorrow. Will defer this decision to the middle shift. Burn
scars will be the most susceptible areas for flash flooding
tomorrow. Doesn't appear to be sufficient instability to maintain
thunderstorms once they move off into the adjacent probability of precipitation
will mainly be confined to the mountain areas and I-25 corridor for
now. Temperatures will remain well below normal Tuesday afternoon. -Kt

Long term...(tuesday night through monday)
issued at 244 PM MDT Monday Jul 6 2015

Mountain convection pushes slowly east Tuesday evening...but suspect
most thunderstorms and rain will weaken quickly east of I-25 as the far eastern
plains remain fairly stable with little cape available. Air mass
Tuesday night/Wednesday morning remains nearly saturated across the
mountains...and with upper wave nearby over northern Colorado/southern
Wyoming...suspect at least scattered convection will continue over the
higher terrain overnight...with lighter showers and sprinkles
over lower elevations/plains. On Wednesday...instability returns to the
plains with pockets of cape over 1000 j/kg...especially far
southeast along the nm and OK borders. Expect mountain convection
to have an easier time spreading eastward across the plains Wednesday
evening/Wednesday night...with some stronger storms possible near the Kansas
border as 0-6km shear climbs into the 30-40 knots range and weak
frontal boundary sags south of the Arkansas River. Maximum temperatures Wednesday
will begin a slow climb...though most areas will remain on the
cool side of middle Summer averages.

Another active day on tap for Thursday as low level temperatures and
subsequent instability increase...with NAM pooling some 1-2k convective available potential energy
along the nm border in the afternoon. Weak energy lifting out of
the southwest U.S. Low will likely provide the trigger for
convection...with potential for some sort of mesoscale convective system rolling east-southeast away
from the mountains and across the plains late Thursday afternoon into
Thursday evening. Temperatures will continue their slow climb...though
clouds/precipitation will keep readings from jumping more than a few degf
most locations.

Air mass will begin to dry out beginning pieces of the
SW upper low eject into the northern Great Basin and upper level high
builds back across the southern rockies. Middle level flow thus takes
on a more west-SW component from Friday afternoon into Sat...allowing a
temporary push of drier air to spread across the state. Will still
have afternoon convection over the mountains...but storms will be
weaker/less extensive than previous days. By sun/Mon...renewed
flow of monsoon moisture begins to arrive under the amplifying
upper ridge...while weak cold front slips southward across the
plains. Should see an increase in convection western areas
sun...than across the remainder of the region early beginning Monday.
With ridge building...maximum temperatures will pop up well into the 80s/90s
most areas Friday into sun before slight cooling develops early next


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 244 PM MDT Monday Jul 6 2015

MVFR ceilings/visible will transition to IFR conditions overnight for the
kcos and kpub terminals with -shra/-tsra possible at times through
the evening. As winds swing around from the southeast
overnight...kcos could see some fog towards morning. MVFR to IFR
ceilings should gradually lift and break during the afternoon for both
terminals. Another round of showers and thunderstorms will develop
over the mountains...a few of which may approach the kcos terminal
during the afternoon producing brief MVFR conditions.

Kals will see -tsra through 23z with potential for erratic gusty
winds. Otherwise winds will remain out of the east overnight with
potential for VFR stratus to persist through the morning hours. If
rainfall occurs at the terminal there will be the potential for IFR
ceilings/visible with fog by morning...but think this scenario is a low
probability will keep ceilings VFR for now. Another round of
thunderstorms can be expected Tuesday afternoon. -Kt


Pub watches/warnings/advisories...


Short term...knots
long term...petersen

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