Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/27/16
Area Forecast Discussion
National Weather Service Pueblo CO
325 PM MDT THU MAY 26 2016
.SHORT TERM...(This evening through Friday)
Issued at 325 PM MDT Thu May 26 2016
...Potential for heavy rain and mountain snows continues into
morning...
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as previously
thought. There certainly could be some enhanced runoff into
fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point.
Should see a pretty good band of rain and higher elevation snow
take shape and move eastward across the plains on Friday as the
upper low pulls eastward with UVV associated with upper level
deformation, along with mid level north to northeast flow
impinging on the eastern mountains. Cooling aloft under the
passing low, with H7 temperatures progged between 0C and 4C across
the area into early tomorrow morning, supports snow levels down
to around 9000 feet before lifting back up to at or above 10K
through the day, with scattered showers and thunderstorms area
wide through the afternoon. Current winter weather highlights
still look good with total snow accumulations of over a foot on
top of Pikes Peak and 2 to 4 inches across the rest of Teller
County, with 4 to locally 8 inches across the higher elevations
of the Sawatch and Mosquito Ranges, and the Sangre de Cristo and
Wet Mountains. The passing system sends a cold front across the
Eastern Plains, with breezy north winds and temps below seasonal
averages expected across the area through the day tomorrow.
.LONG TERM...(Friday night through Thursday)
Issued at 325 PM MDT Thu May 26 2016
Saturday-Sunday...Drier westerly flow aloft across the area Saturday
gives way to increasing southwest flow through the day on Sunday
ahead of an embedded disturbance translating across the southern
Rockies through Sunday night. There will be enough residual moisture
to support isolated to scattered showers and storms across the area
Saturday afternoon and evening, with the best coverage over and near
the higher terrain. There remains some model diffecences on
Sunday, through there looks to be a better chance of showers and
storms expected across the area through the afternoon and
evening, with stronger storms possible across the far SE Plains
with a dry line in the vicinity of western Kansas. Temperatures
look to be at or slightly below seasonal averages through the
weekend.
Monday-Thursday...A relatively cool and unsettled weather pattern
remains in the offing through early next week, as another embedded
disturbance translates across the northern and central Rockies
sends a front across the plains on Monday, with cool upslope flow
persisting across the area on Tuesday. This will keep generally
scattered afternoon and evening showers and storms possible
through the period, with temperatures remaining at or slightly
below seasonal averages.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 325 PM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory until 6 AM MDT Friday for COZ058-060.
Winter Storm Warning until 6 PM MDT Friday for COZ082.
Winter Weather Advisory until noon MDT Friday for COZ073-080.
&&
$$
SHORT TERM...KT/MW
LONG TERM...MW
AVIATION...KT/MW
Area Forecast Discussion
National Weather Service Pueblo CO
1138 AM MDT THU MAY 26 2016
.UPDATE...
Issued at 1023 AM MDT Thu May 26 2016
Models still converging on a farther south position of the cold
front this afternoon which puts more of southeast Colorado under
the threat for severe weather as it lifts back northward. Several
runs now of the HRRR are developing supercell thunderstorms along
the boundary across eastern Las Animas and northern Baca
counties...which track north northeastward through the afternoon.
Pretty good updraft helicity at times with some of these
cells...and they will be in an area of good atmospheric low level helicity
given easterly surface winds beneath southwest flow aloft. Will
have to monitor these for not only a severe thunderstorm
potential...but a tornado potential as well. Other area of concern
will be across El Paso county. Every other run of the HRRR
oscillates between more persistent strong convective regime which
persists through the afternoon...to a scenario of brief severe
convection quickly transitioning over to more stratiform scenario.
Still think there is a window for severe thunderstorm
potential...even an isolated tornado threat through the
afternoon...so forecast leans towards the more convective scenario
for now.
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. Snow levels down to 9000 feet still look on track as do
highlights across the mountains. Should see a pretty good band of
rain take shape and move eastward across the plains on Friday as
the upper low pulls eastward.
For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as
previously thought. There certainly could be some enhanced runoff
into fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point. -KT
&&
.SHORT TERM...(Today and tonight)
Issued at 347 AM MDT Thu May 26 2016
...A POTENTIALLY VERY ACTIVE DAY ACROSS THE FORECAST AREA..
Currently...
Upper closed low which promises to bring active wx to the region
later today and tonight was spinning over nw AZ at 3 am. Over the
immediate area, boundary extended from roughly KSPD to Kim to KPUB
and the banked up along the mtns. North of this boundary winds are
generally east to northeast with dwpts in the 40s...with 50s over
the extreme east. South of this boundary it was much dryer...with
dwpts in the teens and 20s. Low clouds were generally north of
highway 50 mainly in Kiowa county.
Today...
Guidance not in good agreement this morning. shorter range hi res
guidance wants to keep the boundary down towards the Raton Mesa and
moves it only slowly north with time. Other guidance such as the NAM
and GFS move the boundary farther north with time...generally north
of highway 50. The location of this boundary is going to be critical
on where severe thunderstorms develop today. if the boundary remains
farther south...than more of the plains will be under a threat of
severe storms. If the boundary lift north...than less of the region
will be under the threat. As of 3 am...SPC has the svr threat area
mainly north of highway 50. However, as mentioned above...HRRR runs
have been persistent on wanting to keep this boundary down towards
the Raton Mesa, and lifting it north late in the day. Latest runs of
the HRRR does show a few rotating storms on the se Plains later
today.
The next concern for today will be the threat of heavier precip
over the greater Pikes Peak region. All guidance shows heavier
convective precip developing over the Pikes Peak area later this
afternoon, although the guidance has the QPF bullseyes in a variety
of locations. Conceptually...with the closed low moving over the
region and northeasterly 700 mb winds impinging on the Pikes Peak/S
mtn areas, the chance of heavier precip is rather high. The concern
is will the precip fall heavy enough to produce
flooding...especially over the burn scars? Given that the
antecedent conditions are not favorable for flash flooding...I
did not issue any flood hilites for the region, but conditions
will have to be watched closely for the threat of locally heavy
rain over the Waldo burn scar region.
Snow will fall over the highest peaks today. A winter storm warning
is already in effect for Pikes Peak...and have added snow advisories
for the higher elevations of the Wets...N Sangres...and for the C
mtns. The heaviest snow will fall over Pikes Peak.
Tonight...
Severe threat will continue over the far eastern plains, with the
greatest threat along and north of the boundary. Steady precip, with
embedded convection will develop/continue over the greater Pikes
Peak area as strong upslope flow in the lower atmosphere impinges
across this region. it is not out of the question that some areas in
the Pikes Peak area are going to see an inch of liquid...with local
amounts in excess of 2 inches possible. Heavy wet snow will fall
over the highest elevations of both Teller and El Paso counties. I
expect most of the accumulating snow will fall above ~9000 feet.
With the snow levels falling...the threat for flooding over the burn
scar will decrease.
Summarizing...
Severe storms will be possible over the Plains today. The severe
potential will extend includes the I-25 corridor region. I would not
be too surprised if the 1300 UTC SPC DY1 outlook has more of se CO
outlooked for severe weather based on the HRRR output. All severe
convective modes will be possible...with the greatest threat for a
tornado or two along the boundary that will extend across the
Plains. I anticipate a tornado watch will be issued later today for
parts of the plains.
Heavy rains will likely occur across most if not all of the Pikes
Peak region later this afternoon and into tonight. Some convective
heavy rains will likely occur later this afternoon. If one of these
storms develops over the burn scar...than a flash flood threat will
be possible. A flash flood watch may be needed later today for the
burn scar.
heavy snow will fall across the mtns. The heaviest accums will
occur above 9000 feet. The heaviest snow will fall over Pikes Peak.
/Hodanish
.LONG TERM...(Friday through Wednesday)
Issued at 347 AM MDT Thu May 26 2016
...Heavy rain and mountain snows continue Friday morning...
Main concern in the extended will be for Friday morning, as the
upper low tracks straight through southeastern Colorado. Storm looks
fairly dynamic, with h7-h5 flow in the 40-50 Kt range rounding the
low center in the NW quad. Mid level flow will be from the N to
NE...bringing a strong orographic component to the Ern mountain
ranges, and contributing to more widespread moderate to heavy precip
in the 12 through 18Z period Friday. The focus for the heaviest QPF
will be over the southern front range, Wets and Sangres, and the I-
25 corridor. The NAM has another 0.5 inches to inch of precip in
this region Fri morn. Other models not quite as wet, but still in
the 0.25-0.50 inch range. With mid level lapse rates falling rapidly
Fri morning, threat for intense convection will drop, but moderate
steady precip could lead to additional problems for local streams
and poor drainage areas. Snow levels will drop to around 8500-9000
feet Fri morning, then rebound to around 10K feet during the day.
Heavy snow accums likely for Pikes Peak above 11000 feet, and higher
elevations of the West and Sangres. Pikes Peak should see an
additional 4-6 inches Friday, and a couple inches for the other
mountain areas. Total snowfall for Pikes Peak could exceed one
foot. Steady precip will wind down Fri afternoon, but there
should still be widespread showers, particularly over the higher
terrain, through the evening. Temps Friday will be about 15
degrees below average for late May.
After Friday, rest of the forecast period is relatively uneventful,
with daily chances for showers, particularly over the mts, and
temps generally around or slightly below average. Quasi-zonal flow
on Sat will transition to SW flow aloft on Sunday as a weaker low
pressure system begins to move into western CO. This system will
move through late Monday into early Tue, and bring another round of
widespread showers and a few storms to the area. The parent low to
this trough will move through the northern Rockies and High Plains
during the midweek period. The GFS is a bit farther south and
stronger with this system than the ECMWF, and there is a large
ensemble spread by 144 hours and beyond. But it is likely the bulk
of this system will remain to our north. As the trough and
associated cold front passes to the east, the Plains will likely
see another round of showers and storms, some of which could be on
the strong side, in the Tue-Wed time period. Stayed pretty close to
the Blended ensemble-based grids for the latter part of the forecast
period, which progs near to slightly below average temps and low-
sct POPs for the region. Rose
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1133 AM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory from 3 PM this afternoon to 6 AM MDT
Friday for COZ058-060.
Winter Storm Warning from 3 PM this afternoon to 6 PM MDT Friday
for COZ082.
Winter Weather Advisory from 3 PM this afternoon to noon MDT
Friday for COZ073-080.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...ROSE
AVIATION...KT
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
238 PM EDT WED MAY 25 2016
.SYNOPSIS...
Issued at 111 PM EDT Wed May 25 2016
A weak trough moving through an unstable airmass over our area
tonight is expected to cause scattered showers and thunderstorms.
An upper level ridge will move into the area Thursday providing
fair weather. Lows tonight will be in the mid 60s with highs
Thursday in the lower and middle 80s. It will remain warm and
humid through the Memorial Day weekend with chances for showers
and thunderstorms continuing... though most of the weekend should
be dry.
&&
.SHORT TERM...(This Evening through Thursday)
Issued at 235 PM EDT Wed May 25 2016
While ridging conts to dampen acrs the area...lack of discernible
forcing and as yet poor mstr rtn hampering any notable precip
dvlpmnt acrs the wrn lakes this aftn. MCV advg acrs nrn IA sprtg
an arc of isold-sct convn fm ern MN into ne IA and the primary ftr
of note shrt term as secondary MCV noted acrs se MO slides ewd
through srn IN/nrn KY. 12Z ILX raob alludes to a general hostile
environment aloft w/residual warm air in place although some
cooling does take place further west twd DVN ahd of apchg mid lvl
trough. Thus suspect newd advng ll theta-e ridge and wk ll flw
will fail to produce any convn this aftn and have dropped all pop
mention sans extreme west ahd of apchg mid lvl trough. Srn spoke
of btr low-mid lvl forcing shld graze nw zones this evening and
may yet sputter further se within modest theta-e ridge in place
hwvr any sense of a consensus model solution sorely lacking. As
such and in light of 12Z CAMS trends will sway fm prior likely
pops overnight as primary focus aloft shifts up acrs nrn WI.
In wake of this sys...largely subsident wrly ll flw overspreads the
area on Thu and in light of 12Z mos guidance/trends fail to see any
justification to carry a pop mention.
&&
.LONG TERM...(Thursday Night through Wednesday)
Issued at 235 PM EDT Wed May 25 2016
General wwd positioning of large scale upr trough and attendant
sfc fntl zone points to lackluster chcs for organized rainfall
through the pd. No doubt upstream convn w/potential downstream MCS
influences complicate the picture...hwvr given stgr mean flw and
deeper ll mstr plume remains well west invof of sfc fntl zone
through the cntrl plains...it would be careless to embrace
derived blended guidance pops which are clearly way overdone. Thus
as yda will again cap any one pd to a low chc mention at this
point. More fvrbl chcs may arise twd sun aftn/eve pending ewd
extent and timing of robust wave lifting up through the midwest.
Beyond that upr ridge cntrd ovr the wrn atl xpcd to expand nwd
through dy7 and likely to cap off the local environment as new mean
troughing dvlps through the wrn US. Otrws seasonably warm and humid
conds xpcd through much of the pd.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 111 PM EDT Wed May 25 2016
Moderate instability has developed over nrn IL this aftn along/ahead
of a wk shrtwv/sfc trof. This system expected to move across nrn
IN tonight. With just wk instability fcst across ne IN when the
shrtwv moves through, just mentioned showers at FWA tonight, with
contd mention of tstms at SBN where instability expected to be
greater. Low level moistening overnight expected to result in
brief mvfr cigs across the area Wed morning... mixing out by
midday.
&&
.IWX Watches/Warnings/Advisories...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JT
SHORT TERM...T
LONG TERM...T
AVIATION...JT
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Area Forecast Discussion
National Weather Service Indianapolis IN
101 PM EDT WED MAY 25 2016
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 218 AM EDT Wed May 25 2016
Upper disturbances and an increasing moist and unstable atmosphere
will combine to trigger thunderstorm chances today through early
next week.
Temperatures will remain a few degrees above normal through the
period with highs mostly in the lower to mid 80s and lows in the 60s.
&&
.NEAR TERM.../Today and Tonight/
Issued at 1007 AM EDT Wed May 25 2016
Pulled pops back a bit this morning and gradually ramped them up
from midday onward per radar trends and HRRR input. Should see a
gradual increase in convective coverage approach from the west
this afternoon as the next upper level wave moves into the area
and diurnal heating/destabilization is maximized. Remainder of
forecast in good shape. Previous discussion follows.
Issued at 218 AM EDT Wed May 25 2016
Focus for the near term will be on thunderstorm chances as well as
temperatures.
Models continue to be in excellent agreement on the major players
with the 00z run.
Currently...showers and thunderstorms were well southwest of our
southwestern counties as a short wave slowly meanders over that
area. This feature could still touch off a few storms overnight in
that area and this morning a little further to the northeast.
However...the main feature today is expected to be another upper
wave moving through the southwest flow aloft...ejected northeast by
a southern California upper low. This upper disturbance should move
into our northwestern counties shortly after 21z per model
blend...including the RAP. This feature will interact with an
increasingly moist and unstable atmosphere...and modest 25 to 30
knot low level flow. Models are forecasting dew points in the lower
60s and mixed layer CAPEs to 1000 j/kg and higher this afternoon.
This should be enough to touch off scattered thunderstorms across
the forecast area. A few storms could be strong...but the SPC day1
outlook is keeping any severe risk just to our west in the even more
unstable air. The thunderstorms should continue through the night as
the upper wave moves through and with at least weak instability
after sunset and a 25 to 30 knot low level jet. Will keep likely
pops going far north...in closer proximity to the upper wave.
Elsewhere...good chance pops look good.
Should see plenty of convective clouds today but should still see
enough sunshine peaking through from time to time to allow
temperatures to reach the lower to mid 80s for afternoon highs.
Meanwhile...with decent cloud cover and southerly winds staying up
around 10 knots...prefer overnight lows at or slightly warmer than
00z MOS in the mid 60s.
&&
.SHORT TERM.../Thursday through Friday night/
Issued at 218 AM EDT Wed May 25 2016
All eyes will continue to be on thunderstorm chances as the Socal
upper low continues to send upper disturbances our way in the
southwest flow aloft even as it moves to the Central Plains Friday
night. Models have been very consistent with this and also with a
modest but persistent moist Gulf flow through the Ohio Valley and
lower Great Lakes on the back side of a Bermuda High and ahead of a
slow moving to stalled Plains frontal system.
Next disturbance in the southwest wavetrain is harder to pick
out...but it looks like a weak impulse will move through the area
Thursday afternoon. As the wave is more subtle...only went with 40
percent pops. However...models are showing a very unstable
atmosphere with CAPES anywhere from 1500-3000 j/kg...depending on
the model. So...with that kind of potential energy...could see some
strong storms with a lot of cloud to ground lightning. Weaker
dynamics preclude organized severe threat...however.
After Thursday...the remainder of the forecast looks pretty much the
same. Although models have a harder time resolving any weak impulse
that far out...each period should see at least one weak wave and
with the atmosphere remaining moist and unstable...will keep 30-40
percent pops going the rest of the way.
It will remain warm and humid and with the air mass unchanged...will
go with a persistence forecast with highs in the mid 80s and lows in
the mid and upper 60s.
&&
.LONG TERM /Saturday through next Tuesday/...
Issued at 222 AM EDT Wed May 25 2016
Ensembles in good agreement with respect to the overall pattern
during the extended. Mean ridging expected over the eastern parts
of the country with troughing over the west.
An upper disturbance is expected to eject into the western Great
Lakes over the upcoming weekend. Will keep chance PoPs in the
forecast for Saturday and Sunday to cover the passage of this
trough.
By early next week, convective potential may tend to diminish and
become more diurnal in nature as heights rise some, however
ensembles suggest a weakness in the upper ridge/cool pocket may
linger over the Ohio valley. For this reason, will continue to
keep some PoPs going through early next week.
&&
.AVIATION /Discussion for the 251800z tafs/...
Issued at 1251 PM EDT Wed May 25 2016
Mainly VFR conditions are expected this TAF period. Brief MVFR
conditions will be possible with any TSRA that may occur this
afternoon and evening.
GFS suggests a weak short wave over Illinois to progress across
indiana late this afternoon and evening. Forecast soundings
suggest steep lapse rates with large CAPE. Thus expect sct TSRA to
develop along and ahead of the wave during the max heating hours
this afternoon and evening. Uncertainty remains with precise
timing and will update to prevailing as showers and storms
develop.
Patchy Fog may be possible late tonight...particularly in those
areas that get rain. Have included MVFR fog at the TAF sites for
now. A lull in convective activity is expected on Thursday morning
as Indiana should remain between short waves. Time heights
suggest subsidence and forecast soundings are capped through at
least 18z.
&&
.IND Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/NIELD
SHORT TERM...MK
LONG TERM...JAS
AVIATION...JP
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
101 PM CDT WED MAY 25 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 415 AM CDT WED MAY 25 2016
At 4 AM Wednesday morning, a large thunderstorm complex continued to
progress east out of the area. A well-developed MCV was present in
northern parts of this storm complex over far SE Nebraska while a
wake low has developed on the back side. This wake low has been
producing gusts up to 50 mph and will continue to do so as it moves
east although it would seem likely to be near its peak intensity
right now. Additional convective showers and storms were developing
in the convergence zone into east central KS, but this area has been
well worked over and do not anticipate anything more than a few
pockets of heavy rain in this area. Another area of thunderstorms
has been persistently developing in association with the LLJ near
the KS/NE border in north central KS. This area of development is
likely to gradually push a weak cold pool a bit south with
development progressively into northern and northeast KS. However,
it will also be making its way into an area of lesser instability
with the effective convective overturning from early this morning,
and expect the storm development to be sub-severe and any associated
outflow likely not very strong.
As the day goes on, the forecast will once again be complex but
there are at least a few moderate confidence elements to grasp on to
in making the forecast. The first is the outflow incoming from the
north which should set up east to west across the area and then wash
out by mid to late afternoon...although some semblance of it may
remain through late day. The second feature of interest has been
consistently forecast by models over the past few days, and that is a
slightly veered flow owing to the passage of a rather strong short
wave early this morning. This veered flow will cause the dryline to
surge east with a dryline bulge into eastern KS. Most indications
are that this dryline bulge will focus into the local forecast area,
probably over the Flint Hills region just west of Emporia and south
of Manhattan. An area of surface low pressure is also expected to
develop into this area. So, as the afternoon progresses, expect
effective heating to lead to a rather unstable airmass across the
forecast area. This instability is likely to be capped for much of
the day though as those veered winds aloft will bring a slightly
stronger EML into the local area.
What this all leads to is a conditional forecast for severe
thunderstorms. The main question will be if the cap can be broken
with only nebulous large scale lifting mechanisms (and even some
potential for weak subsidence aloft), and only modest convergence
along the dryline. IF thunderstorms are able to develop, it would be
in a very unstable environment with effective shear in the 35-40 kt
range which would be more than sufficient for supercells. It also
seems that if storms develop they would remain relatively discrete
owing to the convective inhibition, and would probably not develop
until peak heating. Thus, any storms that are able to develop can be
expected to become severe with very large hail and locally damaging
winds possible. Veered low level winds are not particularly
supportive of tornadoes, but the potential of a weak remnant outflow
boundary along with localized backing depending on the strength of
the surface meso-low in central KS means there is at least some
tornado potential with any long-lived supercell structures. The best
chance for initiation would be along the nose of that dryline bulge
with storm motion being almost due east.
Later tonight, convective coverage is in question, and it may focus
an area of development over far northeast KS where the LLJ
convergence maximizes in an unstable airmass. If this occurs, could
see areas of heavy rain as well as a continued severe weather threat
through the overnight hours.
.LONG TERM...(Thursday through Tuesday)
Issued at 415 AM CDT WED MAY 25 2016
Main focus for the period in terms of severe weather chances reside
on Thursday afternoon and then on Friday afternoon as the open
trough axis lifts through the central plains. Exact details on
location and timing of convection is still uncertain and dependent
on Wednesday night convection and how quickly it clears which
currently appears during the morning hours. With the system becoming
more negatively tilted during the afternoon on Thursday, winds aloft
are expected to increase while sfc winds back towards the south and
southeast as the sfc low stretches across central KS. The dryline is
the likely trigger for convection to fire in
central KS by late afternoon. These storms are expected to track
eastward towards north central KS during the evening. Second area
for possible convection is along the expected outflow boundary
draped over the area from previous convection. With ample moisture
and available CAPE in excess of 4000 J/KG, it will not take much
forcing to initiate development. By the evening, LLJ increases with
a cluster of storms to center around the warm front near the KS and
NE border. These storms are likely to impact much of the area as the
low level jet veers overnight. Main threats are large hail and
damaging winds. Tornadoes are possible as well,
especially with any discrete cells or in vicinity to a boundary
through early evening. Localized flash flooding is likely given
the excessive rainfall these past few days.
By Friday, upper level dynamics increases as the trough lifts over
central KS, becoming more stacked with the sfc low and attendant
dryline. The dryline is expected to shift east into the CWA,
creating another a decent chance for thunderstorms to develop in the
late afternoon and evening. Shear profiles are sufficient to once
again see all modes of severe weather with decent low level shear
profiles in the early evening near the sfc low over north central
KS.
Highlights for the weekend into mid next week do not change much
from previous forecasts. As upper trough exits northeast Saturday
afternoon, could see additional storms in afternoon. Severe weather
is unlikely as effective shear is pretty weak, less than 20 kts.
Similar scenario is likely from Sunday onward as broad
southwest troughing continues to bring disturbances into the area.
Flash Flooding and River Flooding threats are very high through the
weekend. Rainfall totals through the weekend range from 1-4 inches
or more through Sunday. With little change in airmass, scattered
thunderstorms are possible for each period until perhaps Wednesday
when a cool front may finally bring a relief from the rainfall.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1257 PM CDT WED MAY 25 2016
Outflow boundary from earlier thunderstorms along the Kansas river
at noon time, very near TAF sites. Ceilings should rise to VFR
shortly, while winds could be variable for the next 2 or 3 hours,
particularly at TOP and FOE before the boundary moves back north.
Isolated thunderstorms developing over central KS late this
afternoon may move through or near TAF sites by early evening so
have VCTS for a few hours during that time. Later tonight, moist
airmass could allow fog to form.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barjenbruch
LONG TERM...Prieto
AVIATION...GDP
Area Forecast Discussion
National Weather Service Wichita KS
1247 PM CDT WED MAY 25 2016
.SYNOPSIS...
Issued at 350 AM CDT Wed May 25 2016
Numerous thunderstorms containing torrential rains continue across
Butler, Cowley & Elk Counties at 230 AM where Flood & Flash Flood
Warnings are in effect. Thunderstorms are being sustained by strong
lower-deck theta-e advection enhanced by lift induced by mid-level
shortwave sprinting NE across SE KS. Hourly rainfalls are in the 1
to 3 inch range in extreme Ern Sumner & NW Cowley Counties. The
cloud-to-ground lightning continues to be frequent & dangerous.
&&
.SHORT TERM...(Today through Friday night)
Issued at 350 AM CDT Wed May 25 2016
Forecast Highlight:
More severe thunderstorms possible for SE KS this afternoon & this
evening.
Significant threat for severe thunderstorms with large-very large
hail, winds around 70 mph & tornadoes continues for areas primarily
along & W of I35-I/135 Thu Afternoon & Night.
Today & Tonight:
With the afore-mentioned mid-level shortwave continuing to sprint
NE across the Mid & Upr MS Valley thunderstorms would be greatest
across SE KS where aligned with broad ultra-high octane moisture
axis. Deep-layer shear, more so directional, remains impressive &
with very high instability there`s a continued threat for severe
thunderstorms for SE KS both this afternoon & tonight.
Thu & Thu Night:
The greatest threat for significant severe thunderstorms is still
expected for areas along, and W, of I-35/I-135. A deep upper-deck
trof that`ll push slowly E across AZ & NM will undergo cyclogenesis
as it lifts SLOWLY NE to NE NM, the TX & OK Panhandles & the CO/KS
border. This would induce increased deep-layer ascent over the Wrn
Plains that would transition E toward Central KS. The slow NE lift
of the upper low would of course induce pronounced sfc cyclogenesis
over SE CO & Wrn KS on Thu. This would strengthen the lower-mid
level moist advection across KS with the most pronounced advection
targeting Central parts of OK & KS. This time deep-layer speed
shear would be strong & coupled with respectable directional shear
supercells would once erupt over these areas & move NE. The
supercells should arrive areas along & W of I-35/I-135 late Thu
Afternoon & continue thru the night. SPC has expanded the "Enhanced
Risk" N as far as Srn Nebraska. As such "Severe Thunderstorms With
Large Hail And Damaging Winds" have been assigned to the afore-
mentioned areas.
Fri & Fri Night:
The threat for severe thunderstorms is beginning to increase Fri
Afternoon & Evening. The greatest severe threat would shift slowly
E. For now SPC has assigned "Slight Risk" to E TX & SE OK, but
wouldn`t be surprised if the "Slight Risk" assignment is eventually
spread N across Central & Ern KS. Stay tuned.
.LONG TERM...(Saturday through Tuesday)
Issued at 350 AM CDT Wed May 25 2016
For Sat & Sat Night the GFS & ECMWF continue to agree quite well
with overall pattern, although the ECMWF is bit stronger with the
departing upper-deck shortwave, scheduled to reach the Upper MS
Valley Sat Night. A 2nd upper-deck trof is forecast to move E &
like it`s predecessor it`ll move slowly E & strengthen as it digs
across Srn CA. A "lead" shortwave will eject NE, likely reaching
Wrn OK & Wrn KS Sun Afternoon. As such, there`ll be several rounds
of thunderstorms from Sun Afternoon thru next Tue.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1240 PM CDT Wed May 25 2016
convective potential is the main challenge. Anticipate conditions
will improve to vfr at all sites early this afternoon. Thunderstorms
possible in the vicinity of KSLN/KHUT/kgdb/KICT late afternoon/early
evening near dryline/outflow boundary. KCNU looks to remain well
into the stable area of the outflow boundary. Suspect thunderstorms
will be primarily focused by surface convergence. Given soupy
airmasss, anticipate MVFR/IFR conditions to return later tonight.
-Howerton
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 89 70 87 67 / 10 10 40 50
Hutchinson 89 67 87 66 / 10 10 50 50
Newton 89 69 86 66 / 20 20 40 50
ElDorado 88 70 86 67 / 20 20 30 50
Winfield-KWLD 89 71 87 67 / 20 10 40 50
Russell 89 61 88 62 / 20 10 40 50
Great Bend 89 61 88 63 / 10 10 50 40
Salina 90 67 89 66 / 20 20 40 50
McPherson 89 68 87 66 / 20 10 40 50
Coffeyville 86 71 86 68 / 50 20 30 50
Chanute 86 71 86 67 / 40 20 30 50
Iola 85 71 86 67 / 50 20 30 60
Parsons-KPPF 86 71 86 68 / 50 20 30 50
&&
.ICT Watches/Warnings/Advisories...
None.
&&
$$
SYNOPSIS...EPS
SHORT TERM...EPS
LONG TERM...EPS
AVIATION...PJH
Area Forecast Discussion
National Weather Service Goodland KS
1139 AM MDT WED MAY 25 2016
.UPDATE...
Issued at 1139 AM MDT Wed May 25 2016
With low cloud deck still impacting central portions of the
forecast area...have lowered expected high temps by a few degrees
to account for the lack of decreasing areal coverage. No other
changes at this time.
&&
.SHORT TERM...(Today through Friday night)
Issued at 242 AM MDT Wed May 25 2016
Upper flow will be southwest today/tonight ahead of an upper low
that will move into the 4-corners areas Thursday. The upper low
will move into eastern Colorado Thursday night. The low then moves
into northwest Kansas Friday and into north central Kansas Friday
night. A surface trough will be over northwest Kansas today and
tonight. A surface low will organize over southeast Colorado
Thursday. The surface low will move into northwest Kansas Friday
and then into north central kansas Friday night.
Subsidence will move into the fa this morning behind the exiting
wave. By this afternoon, some lift will develop over an axis of
instability where there will be a slight chance of storms.
Any storms will move northeast with subsidence returning to the fa
early this evening. Late this evening another shortwave will
produce some lift across the northern fa for storms overnight.
Storms will be possible early Thursday and continue Thursday night
and Friday. Dynamics and moisture favor the northwest fa during
this time. By Friday night the focus for storms shifts over the
eastern fa as the low moves east. Shear and cape are both supportive
of severe storms through Friday. Shear and cape drop off Friday
night so that there should be no severe threat and that thunder will
be isolated with showers the dominant type of weather.
STRATUS AND PATCHY FOG HAVE MOVED INTO THE FA EARLY THIS MORNING.
NAM BOUNDARY LAYER RH POINTS OUT THE EXTENT OF THE STRATUS ACROSS
THE FA. CONDITIONS SHOULD IMPROVE BY MID MORNING.
Max temperatures should reach the lower 80s today. Cooler readings
can be expected Thursday ranging from the lower 70s in eastern
Colorado to the lower 80s in the eastern fa. Max temperatures Friday
should range from the mid 60s to the mid 70s. Min temperatures
should be in the lower to mid 50s with some upper 40s in eastern
Colorado.
.LONG TERM...(Saturday through Tuesday)
Issued at 242 AM MDT Wed May 25 2016
At the start of the extended mid level ridging will allow for
periods of dry conditions heading into Saturday. Starting Saturday
night and going through the end of the extended period, expect an
increase chance of rain showers and thunderstorms as shortwaves
will move around the base of approaching upper level low over the
Pacific Northwest/Northern Rockies area.
Temperatures will be in the near to above normal range during the
extended period with highs mainly in the mid to upper 70s, with some
areas reaching the lower 80s. Overnight lows will range in the 50s
with some upper 40s in Northeastern Colorado.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1128 AM MDT Wed May 25 2016
For KGLD...Mainly VFR conditions after 20z-21z. MVFR skies thru
20z-21z...and 3-5sm -shra br from 04z-08z Thursday.
Winds...Variable from the NW thru 21z then SSE 5-10kts...becoming
ENE around 5kts by 08z Thursday as front approaches.
For KMCK...Mainly VFR conditions...w/ some MVFR from 04z-09z
thursday w/ 3-5sm -shra br. Winds ESE around 10kts thru 00z
Thursday...then ENE 5-10kts.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...FS
LONG TERM...BW
AVIATION...JN
Area Forecast Discussion
National Weather Service Dodge City KS
712 AM CDT WED MAY 25 2016
...updated aviation section...
.SHORT TERM...(Today and tonight)
Issued at 424 AM CDT Wed May 25 2016
Quiet weather is likely in southwest Kansas today after the major
severe weather outbreak Tuesday afternoon and evening. An outflow
boundary from the convective cluster in eastern Kansas extended
from south of Medicine Lodge across southwest Kansas into east
central Colorado early this morning, and an area of surface low
pressure was centered near the Colorado/Kansas border south of
GLD. A vigorous upper level trough was evident on satellite
imagery from eastern Montana into eastern Colorado at 08Z. The
surface low should move east into north central Kansas as the
upper level trough progresses into the eastern Dakotas later
today, and low level flow will become southwest as the convective
outflow erodes this morning. Low level moisture will erode during
the day, and a dryline will become established across central
Kansas this afternoon. A minor upper level trough approaching the
Four Corners area will move into northwest Kansas and southern
Nebraska this afternoon, and a few thunderstorms may develop in
the richer low level moisture north of the surface cyclone in
northern Kansas. Other thunderstorms can be expected near the
dryline across central Kansas.
Downslope flow, clearing skies and drier low level air will allow
temperatures this afternoon to rise into the 80s and lower 90s
with the warmest temperatures in the southwest corner of the
state. Temperatures will be modulated downward slightly in areas
that received heavy rainfall Tuesday as a consequence of
evaporation of ponded water. Mostly clear skies and relatively dry
air will allow temperatures tonight to fall back to near seasonal
averages in the 50s and lower 60s.
An upper level cyclone centered near the coast of southern
California this morning will eject northeast as another upper
level trough near the British Columbia coast drops into the
western United States long wave position. This upper level cyclone
should reach eastern Colorado Friday morning. Surface cyclogenesis
will occur in southeast Colorado Thursday as the upper level
cyclone approaches, and low level flow in western Kansas will back
and increase as pressures fall in southeast Colorado. Low level
moisture will surge back into southwest Kansas, but some
uncertainty exists about exactly where the dryline will become
established Thursday afternoon. The current guidance suggests that
the rich low level moisture will spread back at least as far west
as Dodge City. Increasing mid and upper level flow over the rich
moisture east of the dryline will provide an environment favorable
for development of supercell thunderstorms with all of the
attendant severe weather phenomena again Thursday, especially from
Dodge City east. Mesoscale details will become better defined
later, but the potential exists for another outbreak of severe
weather with a few tornadoes Thursday afternoon and evening.
.LONG TERM...(Thursday through Tuesday)
Issued at 424 AM CDT Wed May 25 2016
The upper level cyclone that moves into eastern Colorado Friday
morning will progress slowly across western Kansas into eastern
Nebraska by Saturday morning. The GFS is quicker to eject the
upper level cyclone than the ECMWF and GEM. Given the very blocky
pattern with an upper level cyclone in central Canada, the slower
solution advertised by the ECMWF seems more reasonable. A diffuse
surface cyclone should move slowly into central Kansas Friday
afternoon with a weak Pacific cold front extending into the Texas
Panhandle. Cold air aloft with the upper level cyclone will
provide sufficient instability for thunderstorm development across
much of Kansas Friday. Temperature Friday will be cooler as a
consequence of cloud cover wrapping around the surface cyclone.
Weak ridging behind the upper level trough should keep Saturday
quiet, but another upper level trough rotating around the western
United States mean long wave trough will approach Kansas on Sunday
and support more thunderstorms. Another minor trough should
approach on Monday. Weaker flow should reduce the potential for
significant severe weather, but there may be some threat of severe
weather each day.
Upper level ridging should build over the Rockies the first part
of next week, and a cold front will move across Kansas Tuesday or
Tuesday night as a progressive upper level trough moves across the
Northern Plains and digs toward the Great Lakes. There may be a
few days of meteorologically benign weather next week with north
to northwest anticyclonic flow aloft over the High Plains.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 707 AM CDT Wed May 25 2016
Fog development at DDC and GCK should rapidly diminish this
morning as the surface warms. VFR can then be expected for the
rest of the TAF period once the thin stratus layer also
completely erodes. Convection is not expected today as the dryline
advances further east.
&&
.HYDROLOGY...
Issued at 424 AM CDT Wed May 25 2016
Widespread rainfall estimated by radar to be from three to five
inches in northern Pratt and southern Stafford Counties likely has
resulted in considerable ponding of surface water. Law enforcement
has not reported any significant problems with runoff, and the
soil in that area is sandy and should absorb much of the water. An
areal flood warning will be maintained this morning.
Other heavy rainfall occurred from Edwards County into Pawnee
County and in eastern Lane and western Ness Counties. Although
some small streams likely will be running high, major flooding is
unlikely.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 89 57 88 57 / 0 10 40 40
GCK 90 52 88 53 / 0 10 20 30
EHA 90 54 86 51 / 0 0 10 20
LBL 91 54 89 54 / 0 10 20 20
HYS 87 57 85 60 / 0 0 40 40
P28 90 66 88 64 / 0 0 30 40
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Ruthi
LONG TERM...Ruthi
AVIATION...Russell
HYDROLOGY...Ruthi
Area Forecast Discussion
National Weather Service Wichita KS
658 AM CDT WED MAY 25 2016
.SYNOPSIS...
Issued at 350 AM CDT Wed May 25 2016
Numerous thunderstorms containing torrential rains continue across
Butler, Cowley & Elk Counties at 230 AM where Flood & Flash Flood
Warnings are in effect. Thunderstorms are being sustained by strong
lower-deck theta-e advection enhanced by lift induced by mid-level
shortwave sprinting NE across SE KS. Hourly rainfalls are in the 1
to 3 inch range in extreme Ern Sumner & NW Cowley Counties. The
cloud-to-ground lightning continues to be frequent & dangerous.
&&
.SHORT TERM...(Today through Friday night)
Issued at 350 AM CDT Wed May 25 2016
Forecast Highlight:
More severe thunderstorms possible for SE KS this afternoon & this
evening.
Significant threat for severe thunderstorms with large-very large
hail, winds around 70 mph & tornadoes continues for areas primarily
along & W of I35-I/135 Thu Afternoon & Night.
Today & Tonight:
With the afore-mentioned mid-level shortwave continuing to sprint
NE across the Mid & Upr MS Valley thunderstorms would be greatest
across SE KS where aligned with broad ultra-high octane moisture
axis. Deep-layer shear, more so directional, remains impressive &
with very high instability there`s a continued threat for severe
thunderstorms for SE KS both this afternoon & tonight.
Thu & Thu Night:
The greatest threat for significant severe thunderstorms is still
expected for areas along, and W, of I-35/I-135. A deep upper-deck
trof that`ll push slowly E across AZ & NM will undergo cyclogenesis
as it lifts SLOWLY NE to NE NM, the TX & OK Panhandles & the CO/KS
border. This would induce increased deep-layer ascent over the Wrn
Plains that would transition E toward Central KS. The slow NE lift
of the upper low would of course induce pronounced sfc cyclogenesis
over SE CO & Wrn KS on Thu. This would strengthen the lower-mid
level moist advection across KS with the most pronounced advection
targeting Central parts of OK & KS. This time deep-layer speed
shear would be strong & coupled with respectable directional shear
supercells would once erupt over these areas & move NE. The
supercells should arrive areas along & W of I-35/I-135 late Thu
Afternoon & continue thru the night. SPC has expanded the "Enhanced
Risk" N as far as Srn Nebraska. As such "Severe Thunderstorms With
Large Hail And Damaging Winds" have been assigned to the afore-
mentioned areas.
Fri & Fri Night:
The threat for severe thunderstorms is beginning to increase Fri
Afternoon & Evening. The greatest severe threat would shift slowly
E. For now SPC has assigned "Slight Risk" to E TX & SE OK, but
wouldn`t be surprised if the "Slight Risk" assignment is eventually
spread N across Central & Ern KS. Stay tuned.
.LONG TERM...(Saturday through Tuesday)
Issued at 350 AM CDT Wed May 25 2016
For Sat & Sat Night the GFS & ECMWF continue to agree quite well
with overall pattern, although the ECMWF is bit stronger with the
departing upper-deck shortwave, scheduled to reach the Upper MS
Valley Sat Night. A 2nd upper-deck trof is forecast to move E &
like it`s predecessor it`ll move slowly E & strengthen as it digs
across Srn CA. A "lead" shortwave will eject NE, likely reaching
Wrn OK & Wrn KS Sun Afternoon. As such, there`ll be several rounds
of thunderstorms from Sun Afternoon thru next Tue.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 658 AM CDT Wed May 25 2016
Expect some scattered MVFR CIGS in the wake of the overnight
convective complex. This will lead to some of the lowest CIGS near
KRSL, KGBD and KRSL. Expect the low clouds to dissipate later this
morning with VFR conditions returning to most locations for the
afternoon hours. Will also see some lingering SHRA/TSRA in SE KS as
the complex of storms exits the area this morning.
For the afternoon hours, expect a dry line/boundary to push to near
the KS Turnpike late this afternoon. Could see isolated convection
develop along and east of this boundary for the late afternoon and
evening hours. Think most of the convection will develop well to the
east of the KICT TAF, so will not mention it in KICT just yet. But
will mention it for most of the evening hours for the KCNU Taf with
the isolated storms expected to congeal into a forward propagating
complex of storms that will move east into Wrn MO early on Thu.
Ketcham
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 89 70 87 67 / 10 10 40 50
Hutchinson 89 67 87 66 / 10 10 50 50
Newton 89 69 86 66 / 20 20 40 50
ElDorado 88 70 86 67 / 20 20 30 50
Winfield-KWLD 89 71 87 67 / 20 10 40 50
Russell 89 61 88 62 / 20 10 40 50
Great Bend 89 61 88 63 / 10 10 50 40
Salina 90 67 89 66 / 20 20 40 50
McPherson 89 68 87 66 / 20 10 40 50
Coffeyville 86 71 86 68 / 50 20 30 50
Chanute 86 71 86 67 / 40 20 30 50
Iola 85 71 86 67 / 50 20 30 60
Parsons-KPPF 86 71 86 68 / 50 20 30 50
&&
.ICT Watches/Warnings/Advisories...
None.
&&
$$
SYNOPSIS...EPS
SHORT TERM...EPS
LONG TERM...EPS
AVIATION...BDK
Area Forecast Discussion
National Weather Service Goodland KS
516 AM MDT WED MAY 25 2016
.SHORT TERM...(Today through Friday night)
Issued at 242 AM MDT Wed May 25 2016
Upper flow will be southwest today/tonight ahead of an upper low
that will move into the 4-corners areas Thursday. The upper low
will move into eastern Colorado Thursday night. The low then moves
into northwest Kansas Friday and into northcentral Kansas Friday
night. A surface trough will be over northwest Kansas today and
tonight. A surface low will organize over southeast Colorado
Thursday. The surface low will move into northwest Kansas Friday
and then into northcentral kansas Friday night.
Subsidence will move into the fa this morning behind the exiting
wave. By this afternoon, some lift will develop over an axis of
instability where there will be a slight chance of storms.
Any storms will move northeast with subsidence returning to the fa
early this evening. Late this evening another shortwave will
produce some lift across the northern fa for storms overnight.
Storms will be possible early Thursday and continue Thursday night
and Friday. Dynamics and moisture favor the northwest fa during
this time. By Friday night the focus for storms shifts over the
eastern fa as the low moves east. Shear and cape are both supportive
of severe storms through Friday. Shear and cape drop off Friday
night so that there should be no severe threat and that thunder will
be isolated with showers the dominant type of weather.
STRATUS AND PATCHY FOG HAVE MOVED INTO THE FA EARLY THIS MORNING.
NAM BOUNDARY LAYER RH POINTS OUT THE EXTENT OF THE STRATUS ACROSS
THE FA. CONDITIONS SHOULD IMPROVE BY MID MORNING.
Max temperatures should reach the lower 80s today. Cooler readings
can be expected Thursday ranging from the lower 70s in eastern
Colorado to the lower 80s in the eastern fa. Max temperatures Friday
should range from the mid 60s to the mid 70s. Min temperatures
should be in the lower to mid 50s with some upper 40s in eastern
Colorado.
.LONG TERM...(Saturday through Tuesday)
Issued at 242 AM MDT Wed May 25 2016
At the start of the extended mid level ridging will allow for
periods of dry conditions heading into Saturday. Starting Saturday
night and going through the end of the extended period, expect an
increase chance of rainshowers and thunderstroms as shortwaves will
move around the base of approaching upper level low over the Pacific
Northwest/Northern Rockies area.
Temperatures will be in the near to above normal range during the
extended period with highs mainly in the mid to upper 70s, with some
areas reaching the lower 80s. Overnight lows will range in the 50s
with some upper 40s in Northeastern Colorado.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 508 AM MDT Wed May 25 2016
LIFR CONDITIONS AT KGLD SHOULD IMPROVE AROUND 15Z AS WINDS
TURN NORTHWEST. OTHERWISE CONDITIONS SHOULD BE VFR AT KGLD AND
KMCK FOR THE NEXT 24 HOURS WITH ONLY A SLIGHT CHANCE OF STORMS AT
KMCK THIS AFTERNOON.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...FS
LONG TERM...BW
AVIATION...FS
Area Forecast Discussion
National Weather Service Wichita KS
350 AM CDT WED MAY 25 2016
.SYNOPSIS...
Issued at 350 AM CDT Wed May 25 2016
Numerous thunderstorms containing torrential rains continue across
Butler, Cowley & Elk Counties at 230 AM where Flood & Flash Flood
Warnings are in effect. Thunderstorms are being sustained by strong
lower-deck theta-e advection enhanced by lift induced by mid-level
shortwave sprinting NE across SE KS. Hourly rainfalls are in the 1
to 3 inch range in extreme Ern Sumner & NW Cowley Counties. The
cloud-to-ground lightning continues to be frequent & dangerous.
&&
.SHORT TERM...(Today through Friday night)
Issued at 350 AM CDT Wed May 25 2016
Forecast Highlight:
More severe thunderstorms possible for SE KS this afternoon & this
evening.
Significant threat for severe thunderstorms with large-very large
hail, winds around 70 mph & tornadoes continues for areas primarily
along & W of I35-I/135 Thu Afternoon & Night.
Today & Tonight:
With the afore-mentioned mid-level shortwave continuing to sprint
NE across the Mid & Upr MS Valley thunderstorms would be greatest
across SE KS where aligned with broad ultra-high octane moisture
axis. Deep-layer shear, more so directional, remains impressive &
with very high instability there`s a continued threat for severe
thunderstorms for SE KS both this afternoon & tonight.
Thu & Thu Night:
The greatest threat for significant severe thunderstorms is still
expected for areas along, and W, of I-35/I-135. A deep upper-deck
trof that`ll push slowly E across AZ & NM will undergo cyclogenesis
as it lifts SLOWLY NE to NE NM, the TX & OK Panhandles & the CO/KS
border. This would induce increased deep-layer ascent over the Wrn
Plains that would transition E toward Central KS. The slow NE lift
of the upper low would of course induce pronounced sfc cyclogenesis
over SE CO & Wrn KS on Thu. This would strengthen the lower-mid
level moist advection across KS with the most pronounced advection
targeting Central parts of OK & KS. This time deep-layer speed
shear would be strong & coupled with respectable directional shear
supercells would once erupt over these areas & move NE. The
supercells should arrive areas along & W of I-35/I-135 late Thu
Afternoon & continue thru the night. SPC has expanded the "Enhanced
Risk" N as far as Srn Nebraska. As such "Severe Thunderstorms With
Large Hail And Damaging Winds" have been assigned to the afore-
mentioned areas.
Fri & Fri Night:
The threat for severe thunderstorms is beginning to increase Fri
Afternoon & Evening. The greatest severe threat would shift slowly
E. For now SPC has assigned "Slight Risk" to E TX & SE OK, but
wouldn`t be surprised if the "Slight Risk" assignment is eventually
spread N across Central & Ern KS. Stay tuned.
.LONG TERM...(Saturday through Tuesday)
Issued at 350 AM CDT Wed May 25 2016
For Sat & Sat Night the GFS & ECMWF continue to agree quite well
with overall pattern, although the ECMWF is bit stronger with the
departing upper-deck shortwave, scheduled to reach the Upper MS
Valley Sat Night. A 2nd upper-deck trof is forecast to move E &
like it`s predecessor it`ll move slowly E & strengthen as it digs
across Srn CA. A "lead" shortwave will eject NE, likely reaching
Wrn OK & Wrn KS Sun Afternoon. As such, there`ll be several rounds
of thunderstorms from Sun Afternoon thru next Tue.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1130 PM CDT Tue May 24 2016
Evolving mesoscale convective system over central Kansas will
move east overnight with brief periods of IFR/MVFR VSBYS in
heavy rain and strong, gusty winds. Some MVFR CIGS can also
be expected Wednesday morning. A moist south to southeast wind
will continue on Wednesday and become gusty along and east of
the I-135 corridor. Some late day convection is also possible
though probably more isolated in nature.
KED
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 89 70 87 67 / 10 10 40 50
Hutchinson 89 67 87 66 / 10 10 50 50
Newton 89 69 86 66 / 20 20 40 50
ElDorado 88 70 86 67 / 20 20 30 50
Winfield-KWLD 89 71 87 67 / 20 10 40 50
Russell 89 61 88 62 / 20 10 40 50
Great Bend 89 61 88 63 / 10 10 50 40
Salina 90 67 89 66 / 20 20 40 50
McPherson 89 68 87 66 / 20 10 40 50
Coffeyville 86 71 86 68 / 50 20 30 50
Chanute 86 71 86 67 / 40 20 30 50
Iola 85 71 86 67 / 50 20 30 60
Parsons-KPPF 86 71 86 68 / 50 20 30 50
&&
.ICT Watches/Warnings/Advisories...
None.
&&
$$
SYNOPSIS...EPS
SHORT TERM...EPS
LONG TERM...EPS
AVIATION...KED
Area Forecast Discussion
National Weather Service Goodland KS
246 AM MDT WED MAY 25 2016
.SHORT TERM...(Today through Friday night)
Issued at 242 AM MDT Wed May 25 2016
Upper flow will be southwest today/tonight ahead of an upper low
that will move into the 4-corners areas Thursday. The upper low
will move into eastern Colorado Thursday night. The low then moves
into northwest Kansas Friday and into northcentral Kansas Friday
night. A surface trough will be over northwest Kansas today and
tonight. A surface low will organize over southeast Colorado
Thursday. The surface low will move into northwest Kansas Friday
and then into northcentral kansas Friday night.
Subsidence will move into the fa this morning behind the exiting
wave. By this afternoon, some lift will develop over an axis of
instability where there will be a slight chance of storms.
Any storms will move northeast with subsidence returning to the fa
early this evening. Late this evening another shortwave will
produce some lift across the northern fa for storms overnight.
Storms will be possible early Thursday and continue Thursday night
and Friday. Dynamics and moisture favor the northwest fa during
this time. By Friday night the focus for storms shifts over the
eastern fa as the low moves east. Shear and cape are both supportive
of severe storms through Friday. Shear and cape drop off Friday
night so that there should be no severe threat and that thunder will
be isolated with showers the dominant type of weather.
STRATUS AND PATCHY FOG HAVE MOVED INTO THE FA EARLY THIS MORNING.
NAM BOUNDARY LAYER RH POINTS OUT THE EXTENT OF THE STRATUS ACROSS
THE FA. CONDITIONS SHOULD IMPROVE BY MID MORNING.
Max temperatures should reach the lower 80s today. Cooler readings
can be expected Thursday ranging from the lower 70s in eastern
Colorado to the lower 80s in the eastern fa. Max temperatures Friday
should range from the mid 60s to the mid 70s. Min temperatures
should be in the lower to mid 50s with some upper 40s in eastern
Colorado.
.LONG TERM...(Saturday through Tuesday)
Issued at 242 AM MDT Wed May 25 2016
At the start of the extended mid level ridging will allow for
periods of dry conditions heading into Saturday. Starting Saturday
night and going through the end of the extended period, expect an
increase chance of rainshowers and thunderstroms as shortwaves will
move around the base of approaching upper level low over the Pacific
Northwest/Northern Rockies area.
Temperatures will be in the near to above normal range during the
extended period with highs mainly in the mid to upper 70s, with some
areas reaching the lower 80s. Overnight lows will range in the 50s
with some upper 40s in Northeastern Colorado.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1100 PM MDT Tue May 24 2016
For KGLD...vfr conditions expected through 8z with winds from the
southeast at 10 mph quickly shifting to the southwest. From 9z
through 14z stratus expected with visibilities possibly down to
2sm creating mvfr conditions with winds from the west then
northwest under 10 mph. Cigs improve to vfr by 15z with only a few
clouds at best for the rest of the taf period. Winds expected from
the north 5-10kts around 18z then back all the way around to the
east-southeast for the remainder of the taf period.
For KMCK...vfr conditions expected through 7z with cigs and vis
lowering to mvfr/ifr range through 13z with winds light from the
east. As winds switch around to the northwest cigs improve to vfr
and continue through the rest of the period. Surface winds
generally variable at speeds around 5kts or so.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...FS
LONG TERM...BW
AVIATION...99
Area Forecast Discussion
National Weather Service Dodge City KS
125 AM CDT WED MAY 25 2016
...Updated Aviation Section...
.SHORT TERM...(This evening through Wednesday)
Issued at 300 PM CDT Tue May 24 2016
Focus in the short term is severe weather tonight. Satellite shows cumulus
across southwest Kansas. Sfc analysis shows an old outflow boundary
moving north across the forecast district and a dryline farther to the
southwest. We launched at 19Z special sounding. There is plenty of SBCAPE
with values over 4000 J/kg. The sounding did show a significant cap
in place, but this should erode over time with continued sfc heating.
Wind shear is supportive for supercells with 38 kt of 0-6 km bulk shear
and 21 kt of 0-1 km shear for tornadoes. The 12Z 4 km NAM showed intense
supercells across southwest Kansas with significant updraft helicity.
The HRRR is showing the same thing, although differs in location of
the storms. Convection should form along the boundary across southwest
Kansas (probably from Garden City down to Meade) and then move to the
east through this evening. Threats will include tornadoes (some of which
could be strong), giant hail of 3-4", and outflow winds as the system
could form into a line later on in the evening. The central zones are
most under the gun as far as severe weather is concerned.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 300 PM CDT Tue May 24 2016
The next chance for storms in on Thursday as a wave moves out. Severe
weather is possible once again during the afternoon and evening. The
best chance of storms will be across the eastern zones. Beyond this
we may see another chance of storms next weekend. Temperatures through
the extended period will be on the warm to near normal side.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 123 AM CDT Wed May 25 2016
An outflow boundary from the large convective cluster in central
and eastern Kansas extended from west central Kansas into
northwest Oklahoma at 06Z, and widespread ceilings near 025 can be
expected through at least 08Z. As the outflow erodes later
tonight. flow above the boundary layer will become southwest in
response to falling pressures in the northern plains, and the
stratus should erode before sunrise. Southwest low level winds
around 10 kts will prevail during the daylight hours, and dry air
is likely to spread across all of southwest Kansas. A few cumulus
clouds with bases near 060 should form in the afternoon,
especially near HYS. Thunderstorms today should remain east of the
TAF sites.
Low level dry air will persist Wednesday night at TAF sites,
although low level moisture will spread back west quickly on
Thursday. VFR conditions are expected through at least Thursday
afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 61 89 57 87 / 70 0 0 20
GCK 58 90 52 87 / 40 0 0 20
EHA 53 90 52 86 / 0 0 0 10
LBL 56 91 54 89 / 20 0 0 10
HYS 56 87 57 85 / 70 0 0 50
P28 65 90 66 88 / 70 0 0 50
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...Ruthi
Area Forecast Discussion
National Weather Service Grand Junction CO
312 AM MDT FRI MAY 27 2016
.SHORT TERM...(Today through Saturday)
Issued at 311 AM MDT Fri May 27 2016
A few showers continue this morning due to wraparound flow from
the low that brought the rain and storms yesterday with occasional
snow being reported at the highest elevations. These showers will
weaken as the night progresses but not completely end so you may
see a few raindrops for the morning commute along and south of the
I-70 corridor as well as portions of the San Juans.
While a ridge does build in today, plenty of moisture and daytime
heating will allow another day of showers and storms. Intensity
and coverage will be somewhat less since the area of low pressure, and
forcing it provided, will have shifted well to our east. Like
Thursday, convection should start firing around noon and continue
through sunset with some spotty showers continuing through
midnight.
Flow becomes more zonal Saturday as a weak wave moves over the
region allowing another afternoon and evening of unsettled
weather. Models paint precip over the highest terrain which looks
good as steering winds are quite weak during this timeframe.
Outside of those areas, partly cloudy skies are expected with
temperatures finally reaching more normal values.
.LONG TERM...(Saturday night through Thursday)
Issued at 334 PM MDT Thu May 26 2016
The long wave trough will reload along the west coast during the
weekend as the next low pressure disturbance develops over
southern California. The flow over our area will quickly become
southwest again by Sat. This relatively unstable flow will carry
enough moisture to keep afternoon convection in the
forecast, mainly along the mountains.
Models show this low weakening as it gradually tracks east early
in the work week. Also a stronger low center over the Pacific
northwest will shift east. As both of these features head east,
high pressure will develop along the west coast. So continued
mainly mountain convection can be expected each afternoon through
Tue. Then the west coast ridge will strengthen and move into the
Great Basin for warmer and drier conditions midweek and beyond.
Temperatures are expected to be a tad below normal during the
weekend, then right around normal through the first half of the
work week. Temps will then climb to just a tad above normal by
the end of the period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 311 AM MDT Fri May 27 2016
Mid level clouds continue to hang around this morning with cigs
varying from about 3.5K feet at ASE up to 10K feet at DRO. Cigs
should lift through the morning hours as the low pressure to our
east continues moving in that direction. A few showers will likely
persist though so those TAF sites near and under the showers may see
the lower cigs persist. KASE...KEGE...KTEX...KRIL and KGJT look to
have the best chance for this to occur. vcsh looks safe for those
sites for the next few hours until some clearing occurs. After
18z...more convection is expected though coverage will be less.
Not sold on any one TAF site actually seeing a -tsra on station so
will leave out for now. By 02z...most convection will end though
some stray showers will persist. Even mentioning the convection
and showery precip, still expect mostly vfr conditions today.
&&
.GJT Watches/Warnings/Advisories...
CO...Winter Weather Advisory until 6 AM MDT early this morning for
COZ010-012.
UT...None.
&&
$$
SHORT TERM...TGR
LONG TERM...EH
AVIATION...TGR
[top]
Area Forecast Discussion
National Weather Service Pueblo CO
325 PM MDT THU MAY 26 2016
.SHORT TERM...(This evening through Friday)
Issued at 325 PM MDT Thu May 26 2016
...Potential for heavy rain and mountain snows continues into
morning...
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as previously
thought. There certainly could be some enhanced runoff into
fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point.
Should see a pretty good band of rain and higher elevation snow
take shape and move eastward across the plains on Friday as the
upper low pulls eastward with UVV associated with upper level
deformation, along with mid level north to northeast flow
impinging on the eastern mountains. Cooling aloft under the
passing low, with H7 temperatures progged between 0C and 4C across
the area into early tomorrow morning, supports snow levels down
to around 9000 feet before lifting back up to at or above 10K
through the day, with scattered showers and thunderstorms area
wide through the afternoon. Current winter weather highlights
still look good with total snow accumulations of over a foot on
top of Pikes Peak and 2 to 4 inches across the rest of Teller
County, with 4 to locally 8 inches across the higher elevations
of the Sawatch and Mosquito Ranges, and the Sangre de Cristo and
Wet Mountains. The passing system sends a cold front across the
Eastern Plains, with breezy north winds and temps below seasonal
averages expected across the area through the day tomorrow.
.LONG TERM...(Friday night through Thursday)
Issued at 325 PM MDT Thu May 26 2016
Saturday-Sunday...Drier westerly flow aloft across the area Saturday
gives way to increasing southwest flow through the day on Sunday
ahead of an embedded disturbance translating across the southern
Rockies through Sunday night. There will be enough residual moisture
to support isolated to scattered showers and storms across the area
Saturday afternoon and evening, with the best coverage over and near
the higher terrain. There remains some model diffecences on
Sunday, through there looks to be a better chance of showers and
storms expected across the area through the afternoon and
evening, with stronger storms possible across the far SE Plains
with a dry line in the vicinity of western Kansas. Temperatures
look to be at or slightly below seasonal averages through the
weekend.
Monday-Thursday...A relatively cool and unsettled weather pattern
remains in the offing through early next week, as another embedded
disturbance translates across the northern and central Rockies
sends a front across the plains on Monday, with cool upslope flow
persisting across the area on Tuesday. This will keep generally
scattered afternoon and evening showers and storms possible
through the period, with temperatures remaining at or slightly
below seasonal averages.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 325 PM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory until 6 AM MDT Friday for COZ058-060.
Winter Storm Warning until 6 PM MDT Friday for COZ082.
Winter Weather Advisory until noon MDT Friday for COZ073-080.
&&
$$
SHORT TERM...KT/MW
LONG TERM...MW
AVIATION...KT/MW
Area Forecast Discussion
National Weather Service Pueblo CO
1138 AM MDT THU MAY 26 2016
.UPDATE...
Issued at 1023 AM MDT Thu May 26 2016
Models still converging on a farther south position of the cold
front this afternoon which puts more of southeast Colorado under
the threat for severe weather as it lifts back northward. Several
runs now of the HRRR are developing supercell thunderstorms along
the boundary across eastern Las Animas and northern Baca
counties...which track north northeastward through the afternoon.
Pretty good updraft helicity at times with some of these
cells...and they will be in an area of good atmospheric low level helicity
given easterly surface winds beneath southwest flow aloft. Will
have to monitor these for not only a severe thunderstorm
potential...but a tornado potential as well. Other area of concern
will be across El Paso county. Every other run of the HRRR
oscillates between more persistent strong convective regime which
persists through the afternoon...to a scenario of brief severe
convection quickly transitioning over to more stratiform scenario.
Still think there is a window for severe thunderstorm
potential...even an isolated tornado threat through the
afternoon...so forecast leans towards the more convective scenario
for now.
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. Snow levels down to 9000 feet still look on track as do
highlights across the mountains. Should see a pretty good band of
rain take shape and move eastward across the plains on Friday as
the upper low pulls eastward.
For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as
previously thought. There certainly could be some enhanced runoff
into fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point. -KT
&&
.SHORT TERM...(Today and tonight)
Issued at 347 AM MDT Thu May 26 2016
...A POTENTIALLY VERY ACTIVE DAY ACROSS THE FORECAST AREA..
Currently...
Upper closed low which promises to bring active wx to the region
later today and tonight was spinning over nw AZ at 3 am. Over the
immediate area, boundary extended from roughly KSPD to Kim to KPUB
and the banked up along the mtns. North of this boundary winds are
generally east to northeast with dwpts in the 40s...with 50s over
the extreme east. South of this boundary it was much dryer...with
dwpts in the teens and 20s. Low clouds were generally north of
highway 50 mainly in Kiowa county.
Today...
Guidance not in good agreement this morning. shorter range hi res
guidance wants to keep the boundary down towards the Raton Mesa and
moves it only slowly north with time. Other guidance such as the NAM
and GFS move the boundary farther north with time...generally north
of highway 50. The location of this boundary is going to be critical
on where severe thunderstorms develop today. if the boundary remains
farther south...than more of the plains will be under a threat of
severe storms. If the boundary lift north...than less of the region
will be under the threat. As of 3 am...SPC has the svr threat area
mainly north of highway 50. However, as mentioned above...HRRR runs
have been persistent on wanting to keep this boundary down towards
the Raton Mesa, and lifting it north late in the day. Latest runs of
the HRRR does show a few rotating storms on the se Plains later
today.
The next concern for today will be the threat of heavier precip
over the greater Pikes Peak region. All guidance shows heavier
convective precip developing over the Pikes Peak area later this
afternoon, although the guidance has the QPF bullseyes in a variety
of locations. Conceptually...with the closed low moving over the
region and northeasterly 700 mb winds impinging on the Pikes Peak/S
mtn areas, the chance of heavier precip is rather high. The concern
is will the precip fall heavy enough to produce
flooding...especially over the burn scars? Given that the
antecedent conditions are not favorable for flash flooding...I
did not issue any flood hilites for the region, but conditions
will have to be watched closely for the threat of locally heavy
rain over the Waldo burn scar region.
Snow will fall over the highest peaks today. A winter storm warning
is already in effect for Pikes Peak...and have added snow advisories
for the higher elevations of the Wets...N Sangres...and for the C
mtns. The heaviest snow will fall over Pikes Peak.
Tonight...
Severe threat will continue over the far eastern plains, with the
greatest threat along and north of the boundary. Steady precip, with
embedded convection will develop/continue over the greater Pikes
Peak area as strong upslope flow in the lower atmosphere impinges
across this region. it is not out of the question that some areas in
the Pikes Peak area are going to see an inch of liquid...with local
amounts in excess of 2 inches possible. Heavy wet snow will fall
over the highest elevations of both Teller and El Paso counties. I
expect most of the accumulating snow will fall above ~9000 feet.
With the snow levels falling...the threat for flooding over the burn
scar will decrease.
Summarizing...
Severe storms will be possible over the Plains today. The severe
potential will extend includes the I-25 corridor region. I would not
be too surprised if the 1300 UTC SPC DY1 outlook has more of se CO
outlooked for severe weather based on the HRRR output. All severe
convective modes will be possible...with the greatest threat for a
tornado or two along the boundary that will extend across the
Plains. I anticipate a tornado watch will be issued later today for
parts of the plains.
Heavy rains will likely occur across most if not all of the Pikes
Peak region later this afternoon and into tonight. Some convective
heavy rains will likely occur later this afternoon. If one of these
storms develops over the burn scar...than a flash flood threat will
be possible. A flash flood watch may be needed later today for the
burn scar.
heavy snow will fall across the mtns. The heaviest accums will
occur above 9000 feet. The heaviest snow will fall over Pikes Peak.
/Hodanish
.LONG TERM...(Friday through Wednesday)
Issued at 347 AM MDT Thu May 26 2016
...Heavy rain and mountain snows continue Friday morning...
Main concern in the extended will be for Friday morning, as the
upper low tracks straight through southeastern Colorado. Storm looks
fairly dynamic, with h7-h5 flow in the 40-50 Kt range rounding the
low center in the NW quad. Mid level flow will be from the N to
NE...bringing a strong orographic component to the Ern mountain
ranges, and contributing to more widespread moderate to heavy precip
in the 12 through 18Z period Friday. The focus for the heaviest QPF
will be over the southern front range, Wets and Sangres, and the I-
25 corridor. The NAM has another 0.5 inches to inch of precip in
this region Fri morn. Other models not quite as wet, but still in
the 0.25-0.50 inch range. With mid level lapse rates falling rapidly
Fri morning, threat for intense convection will drop, but moderate
steady precip could lead to additional problems for local streams
and poor drainage areas. Snow levels will drop to around 8500-9000
feet Fri morning, then rebound to around 10K feet during the day.
Heavy snow accums likely for Pikes Peak above 11000 feet, and higher
elevations of the West and Sangres. Pikes Peak should see an
additional 4-6 inches Friday, and a couple inches for the other
mountain areas. Total snowfall for Pikes Peak could exceed one
foot. Steady precip will wind down Fri afternoon, but there
should still be widespread showers, particularly over the higher
terrain, through the evening. Temps Friday will be about 15
degrees below average for late May.
After Friday, rest of the forecast period is relatively uneventful,
with daily chances for showers, particularly over the mts, and
temps generally around or slightly below average. Quasi-zonal flow
on Sat will transition to SW flow aloft on Sunday as a weaker low
pressure system begins to move into western CO. This system will
move through late Monday into early Tue, and bring another round of
widespread showers and a few storms to the area. The parent low to
this trough will move through the northern Rockies and High Plains
during the midweek period. The GFS is a bit farther south and
stronger with this system than the ECMWF, and there is a large
ensemble spread by 144 hours and beyond. But it is likely the bulk
of this system will remain to our north. As the trough and
associated cold front passes to the east, the Plains will likely
see another round of showers and storms, some of which could be on
the strong side, in the Tue-Wed time period. Stayed pretty close to
the Blended ensemble-based grids for the latter part of the forecast
period, which progs near to slightly below average temps and low-
sct POPs for the region. Rose
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1133 AM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory from 3 PM this afternoon to 6 AM MDT
Friday for COZ058-060.
Winter Storm Warning from 3 PM this afternoon to 6 PM MDT Friday
for COZ082.
Winter Weather Advisory from 3 PM this afternoon to noon MDT
Friday for COZ073-080.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...ROSE
AVIATION...KT
Area Forecast Discussion
National Weather Service Grand Junction CO
312 AM MDT FRI MAY 27 2016
.SHORT TERM...(Today through Saturday)
Issued at 311 AM MDT Fri May 27 2016
A few showers continue this morning due to wraparound flow from
the low that brought the rain and storms yesterday with occasional
snow being reported at the highest elevations. These showers will
weaken as the night progresses but not completely end so you may
see a few raindrops for the morning commute along and south of the
I-70 corridor as well as portions of the San Juans.
While a ridge does build in today, plenty of moisture and daytime
heating will allow another day of showers and storms. Intensity
and coverage will be somewhat less since the area of low pressure, and
forcing it provided, will have shifted well to our east. Like
Thursday, convection should start firing around noon and continue
through sunset with some spotty showers continuing through
midnight.
Flow becomes more zonal Saturday as a weak wave moves over the
region allowing another afternoon and evening of unsettled
weather. Models paint precip over the highest terrain which looks
good as steering winds are quite weak during this timeframe.
Outside of those areas, partly cloudy skies are expected with
temperatures finally reaching more normal values.
.LONG TERM...(Saturday night through Thursday)
Issued at 334 PM MDT Thu May 26 2016
The long wave trough will reload along the west coast during the
weekend as the next low pressure disturbance develops over
southern California. The flow over our area will quickly become
southwest again by Sat. This relatively unstable flow will carry
enough moisture to keep afternoon convection in the
forecast, mainly along the mountains.
Models show this low weakening as it gradually tracks east early
in the work week. Also a stronger low center over the Pacific
northwest will shift east. As both of these features head east,
high pressure will develop along the west coast. So continued
mainly mountain convection can be expected each afternoon through
Tue. Then the west coast ridge will strengthen and move into the
Great Basin for warmer and drier conditions midweek and beyond.
Temperatures are expected to be a tad below normal during the
weekend, then right around normal through the first half of the
work week. Temps will then climb to just a tad above normal by
the end of the period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 311 AM MDT Fri May 27 2016
Mid level clouds continue to hang around this morning with cigs
varying from about 3.5K feet at ASE up to 10K feet at DRO. Cigs
should lift through the morning hours as the low pressure to our
east continues moving in that direction. A few showers will likely
persist though so those TAF sites near and under the showers may see
the lower cigs persist. KASE...KEGE...KTEX...KRIL and KGJT look to
have the best chance for this to occur. vcsh looks safe for those
sites for the next few hours until some clearing occurs. After
18z...more convection is expected though coverage will be less.
Not sold on any one TAF site actually seeing a -tsra on station so
will leave out for now. By 02z...most convection will end though
some stray showers will persist. Even mentioning the convection
and showery precip, still expect mostly vfr conditions today.
&&
.GJT Watches/Warnings/Advisories...
CO...Winter Weather Advisory until 6 AM MDT early this morning for
COZ010-012.
UT...None.
&&
$$
SHORT TERM...TGR
LONG TERM...EH
AVIATION...TGR
[top]
Area Forecast Discussion
National Weather Service Pueblo CO
325 PM MDT THU MAY 26 2016
.SHORT TERM...(This evening through Friday)
Issued at 325 PM MDT Thu May 26 2016
...Potential for heavy rain and mountain snows continues into
morning...
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as previously
thought. There certainly could be some enhanced runoff into
fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point.
Should see a pretty good band of rain and higher elevation snow
take shape and move eastward across the plains on Friday as the
upper low pulls eastward with UVV associated with upper level
deformation, along with mid level north to northeast flow
impinging on the eastern mountains. Cooling aloft under the
passing low, with H7 temperatures progged between 0C and 4C across
the area into early tomorrow morning, supports snow levels down
to around 9000 feet before lifting back up to at or above 10K
through the day, with scattered showers and thunderstorms area
wide through the afternoon. Current winter weather highlights
still look good with total snow accumulations of over a foot on
top of Pikes Peak and 2 to 4 inches across the rest of Teller
County, with 4 to locally 8 inches across the higher elevations
of the Sawatch and Mosquito Ranges, and the Sangre de Cristo and
Wet Mountains. The passing system sends a cold front across the
Eastern Plains, with breezy north winds and temps below seasonal
averages expected across the area through the day tomorrow.
.LONG TERM...(Friday night through Thursday)
Issued at 325 PM MDT Thu May 26 2016
Saturday-Sunday...Drier westerly flow aloft across the area Saturday
gives way to increasing southwest flow through the day on Sunday
ahead of an embedded disturbance translating across the southern
Rockies through Sunday night. There will be enough residual moisture
to support isolated to scattered showers and storms across the area
Saturday afternoon and evening, with the best coverage over and near
the higher terrain. There remains some model diffecences on
Sunday, through there looks to be a better chance of showers and
storms expected across the area through the afternoon and
evening, with stronger storms possible across the far SE Plains
with a dry line in the vicinity of western Kansas. Temperatures
look to be at or slightly below seasonal averages through the
weekend.
Monday-Thursday...A relatively cool and unsettled weather pattern
remains in the offing through early next week, as another embedded
disturbance translates across the northern and central Rockies
sends a front across the plains on Monday, with cool upslope flow
persisting across the area on Tuesday. This will keep generally
scattered afternoon and evening showers and storms possible
through the period, with temperatures remaining at or slightly
below seasonal averages.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 325 PM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory until 6 AM MDT Friday for COZ058-060.
Winter Storm Warning until 6 PM MDT Friday for COZ082.
Winter Weather Advisory until noon MDT Friday for COZ073-080.
&&
$$
SHORT TERM...KT/MW
LONG TERM...MW
AVIATION...KT/MW
Area Forecast Discussion
National Weather Service Pueblo CO
1138 AM MDT THU MAY 26 2016
.UPDATE...
Issued at 1023 AM MDT Thu May 26 2016
Models still converging on a farther south position of the cold
front this afternoon which puts more of southeast Colorado under
the threat for severe weather as it lifts back northward. Several
runs now of the HRRR are developing supercell thunderstorms along
the boundary across eastern Las Animas and northern Baca
counties...which track north northeastward through the afternoon.
Pretty good updraft helicity at times with some of these
cells...and they will be in an area of good atmospheric low level helicity
given easterly surface winds beneath southwest flow aloft. Will
have to monitor these for not only a severe thunderstorm
potential...but a tornado potential as well. Other area of concern
will be across El Paso county. Every other run of the HRRR
oscillates between more persistent strong convective regime which
persists through the afternoon...to a scenario of brief severe
convection quickly transitioning over to more stratiform scenario.
Still think there is a window for severe thunderstorm
potential...even an isolated tornado threat through the
afternoon...so forecast leans towards the more convective scenario
for now.
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. Snow levels down to 9000 feet still look on track as do
highlights across the mountains. Should see a pretty good band of
rain take shape and move eastward across the plains on Friday as
the upper low pulls eastward.
For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as
previously thought. There certainly could be some enhanced runoff
into fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point. -KT
&&
.SHORT TERM...(Today and tonight)
Issued at 347 AM MDT Thu May 26 2016
...A POTENTIALLY VERY ACTIVE DAY ACROSS THE FORECAST AREA..
Currently...
Upper closed low which promises to bring active wx to the region
later today and tonight was spinning over nw AZ at 3 am. Over the
immediate area, boundary extended from roughly KSPD to Kim to KPUB
and the banked up along the mtns. North of this boundary winds are
generally east to northeast with dwpts in the 40s...with 50s over
the extreme east. South of this boundary it was much dryer...with
dwpts in the teens and 20s. Low clouds were generally north of
highway 50 mainly in Kiowa county.
Today...
Guidance not in good agreement this morning. shorter range hi res
guidance wants to keep the boundary down towards the Raton Mesa and
moves it only slowly north with time. Other guidance such as the NAM
and GFS move the boundary farther north with time...generally north
of highway 50. The location of this boundary is going to be critical
on where severe thunderstorms develop today. if the boundary remains
farther south...than more of the plains will be under a threat of
severe storms. If the boundary lift north...than less of the region
will be under the threat. As of 3 am...SPC has the svr threat area
mainly north of highway 50. However, as mentioned above...HRRR runs
have been persistent on wanting to keep this boundary down towards
the Raton Mesa, and lifting it north late in the day. Latest runs of
the HRRR does show a few rotating storms on the se Plains later
today.
The next concern for today will be the threat of heavier precip
over the greater Pikes Peak region. All guidance shows heavier
convective precip developing over the Pikes Peak area later this
afternoon, although the guidance has the QPF bullseyes in a variety
of locations. Conceptually...with the closed low moving over the
region and northeasterly 700 mb winds impinging on the Pikes Peak/S
mtn areas, the chance of heavier precip is rather high. The concern
is will the precip fall heavy enough to produce
flooding...especially over the burn scars? Given that the
antecedent conditions are not favorable for flash flooding...I
did not issue any flood hilites for the region, but conditions
will have to be watched closely for the threat of locally heavy
rain over the Waldo burn scar region.
Snow will fall over the highest peaks today. A winter storm warning
is already in effect for Pikes Peak...and have added snow advisories
for the higher elevations of the Wets...N Sangres...and for the C
mtns. The heaviest snow will fall over Pikes Peak.
Tonight...
Severe threat will continue over the far eastern plains, with the
greatest threat along and north of the boundary. Steady precip, with
embedded convection will develop/continue over the greater Pikes
Peak area as strong upslope flow in the lower atmosphere impinges
across this region. it is not out of the question that some areas in
the Pikes Peak area are going to see an inch of liquid...with local
amounts in excess of 2 inches possible. Heavy wet snow will fall
over the highest elevations of both Teller and El Paso counties. I
expect most of the accumulating snow will fall above ~9000 feet.
With the snow levels falling...the threat for flooding over the burn
scar will decrease.
Summarizing...
Severe storms will be possible over the Plains today. The severe
potential will extend includes the I-25 corridor region. I would not
be too surprised if the 1300 UTC SPC DY1 outlook has more of se CO
outlooked for severe weather based on the HRRR output. All severe
convective modes will be possible...with the greatest threat for a
tornado or two along the boundary that will extend across the
Plains. I anticipate a tornado watch will be issued later today for
parts of the plains.
Heavy rains will likely occur across most if not all of the Pikes
Peak region later this afternoon and into tonight. Some convective
heavy rains will likely occur later this afternoon. If one of these
storms develops over the burn scar...than a flash flood threat will
be possible. A flash flood watch may be needed later today for the
burn scar.
heavy snow will fall across the mtns. The heaviest accums will
occur above 9000 feet. The heaviest snow will fall over Pikes Peak.
/Hodanish
.LONG TERM...(Friday through Wednesday)
Issued at 347 AM MDT Thu May 26 2016
...Heavy rain and mountain snows continue Friday morning...
Main concern in the extended will be for Friday morning, as the
upper low tracks straight through southeastern Colorado. Storm looks
fairly dynamic, with h7-h5 flow in the 40-50 Kt range rounding the
low center in the NW quad. Mid level flow will be from the N to
NE...bringing a strong orographic component to the Ern mountain
ranges, and contributing to more widespread moderate to heavy precip
in the 12 through 18Z period Friday. The focus for the heaviest QPF
will be over the southern front range, Wets and Sangres, and the I-
25 corridor. The NAM has another 0.5 inches to inch of precip in
this region Fri morn. Other models not quite as wet, but still in
the 0.25-0.50 inch range. With mid level lapse rates falling rapidly
Fri morning, threat for intense convection will drop, but moderate
steady precip could lead to additional problems for local streams
and poor drainage areas. Snow levels will drop to around 8500-9000
feet Fri morning, then rebound to around 10K feet during the day.
Heavy snow accums likely for Pikes Peak above 11000 feet, and higher
elevations of the West and Sangres. Pikes Peak should see an
additional 4-6 inches Friday, and a couple inches for the other
mountain areas. Total snowfall for Pikes Peak could exceed one
foot. Steady precip will wind down Fri afternoon, but there
should still be widespread showers, particularly over the higher
terrain, through the evening. Temps Friday will be about 15
degrees below average for late May.
After Friday, rest of the forecast period is relatively uneventful,
with daily chances for showers, particularly over the mts, and
temps generally around or slightly below average. Quasi-zonal flow
on Sat will transition to SW flow aloft on Sunday as a weaker low
pressure system begins to move into western CO. This system will
move through late Monday into early Tue, and bring another round of
widespread showers and a few storms to the area. The parent low to
this trough will move through the northern Rockies and High Plains
during the midweek period. The GFS is a bit farther south and
stronger with this system than the ECMWF, and there is a large
ensemble spread by 144 hours and beyond. But it is likely the bulk
of this system will remain to our north. As the trough and
associated cold front passes to the east, the Plains will likely
see another round of showers and storms, some of which could be on
the strong side, in the Tue-Wed time period. Stayed pretty close to
the Blended ensemble-based grids for the latter part of the forecast
period, which progs near to slightly below average temps and low-
sct POPs for the region. Rose
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1133 AM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory from 3 PM this afternoon to 6 AM MDT
Friday for COZ058-060.
Winter Storm Warning from 3 PM this afternoon to 6 PM MDT Friday
for COZ082.
Winter Weather Advisory from 3 PM this afternoon to noon MDT
Friday for COZ073-080.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...ROSE
AVIATION...KT
Area Forecast Discussion
National Weather Service Pueblo CO
319 PM MDT FRI MAY 27 2016
.SHORT TERM...(This evening through Saturday)
Issued at 319 PM MDT Fri May 27 2016
Rest of today...Upper low over eastern CO and western KS will
continue to pull off to the northeast. Area of showers and
thunderstorms has been developing in area of wrap around...with
most intense cells in southern CO developing across Kiowa county.
High res models continue to show best activity across far northeast
sections of that area through late afternoon and early evening before
activity pulls off to the northeast and diminishes overnight.
Main threat will be local wind gusts to around 50 mph along with
some small hail.
Remainder of the area could see some scattered showers and isolated
embedded thunderstorms this afternoon through early
evening...particularly over the mountains but these too should
diminish with loss of heating. Elsewhere, gusty north to northwest
winds will continue across the plains into the early evening, before
winds weaken overnight.
For tomorrow...weather looks much more quiet with shortwave ridging
aloft. There will still be sufficient moisture for thunderstorms,
particularly in and near the mountains. However, limited
instability, with CAPE values generally around 500 J/KG, storms
will remain on the weaker side, with gusty winds up to 50 mph and
lightning being the primary storm threats. Storms will initiate
over the higher terrain before slowly moving across the plains
during the afternoon and evening hours. High temperatures across
the plains will rebound back into the upper 70s with mid to upper-
60s expected across the high valleys. Overnight, temperatures will
be on the cooler side with lows approaching the freezing mark in
the San Luis Valley.
.LONG TERM...(Saturday night through Friday)
Issued at 319 PM MDT Fri May 27 2016
Saturday night-Sunday night...Drier westerly flow aloft across the
area Saturday gives way to increasing southwest flow Saturday night
and Sunday ahead of an embedded disturbance translating across the
southern Rockies through Sunday night. Some differences in models on
location of this embedded disturbance with the latest NAM and GFS
seemingly overdone with WAA precipitation across the far southeast
plains Saturday night. At any rate, isolated to scattered showers
and thunderstorms across the area Saturday afternoon to diminish
through the evening, though did keep slight pops across the far se
plains through the overnight hours. Increasing UVV and moisture
ahead of the southern Rockies wave looks to bring a better chance of
showers and storms across the area Sunday afternoon and evening,
with stronger storms still possible across the far SE Plains, as lee
troughing across the southeast plains helps dry line across western
Kansas to retrograde. Temperatures look to warm back to around
seasonal averages by Sunday.
Monday-Wednesday...A relatively cool and unsettled weather pattern
remains in the offing through the middle of next week, as more
energy translates across the southern Rockies, with another upper
wave slowly digging across the northern Rockies Monday and into the
central High Plains through Wednesday. There are some differences in
model location and timing of features, though a cold front looks to
move across the plains late Monday night and through the day
Tuesday, supporting the potential for possible severe weather and
locally heavy rainfall Tuesday and Wednesday. Could also see some
more higher elevation snowfall through this period, depending on the
track of the upper level features.
Thursday-Friday...A slow warming and drying trend for late next week
as upper level ridging across the Desert Southwest and Great Basin
is progged to build into the Rockies.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 319 PM MDT Fri May 27 2016
VFR conditions are expected at the TAF sites throughout the period.
Winds will continue to remain gusty at KPUB and KCOS through 02Z,
before winds decrease overnight. A few showers will continue to
linger around KPUB and KCOS through about 03Z before activity
diminishes overnight. Showers and thunderstorms will form over the
higher terrain starting around 17-18Z tomorrow afternoon. KALS and
KCOS may see VCTS starting around 20Z.
&&
.PUB Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
[top]
Area Forecast Discussion
National Weather Service Denver/Boulder CO
1248 PM MDT FRI MAY 27 2016
.UPDATE...
Issued at 1204 pM MDT Fri May 27 2016
The suns heating over the far northeast corner of the state has
allowed for some additional destabilization. May see a stronger
storm east of a line from Sterling to Limon. The main threat from
these storms would be hail up to an inch and possible gusty
outflow winds to 40 mph.
UPDATE Issued at 1041 AM MDT Fri May 27 2016
The band of rain across the eastern plains is decreasing in area
as well as intensity late this morning. The band is slowly moving
west but is expected to continue to weaken. Rainfall rates will
likely be below a tenth of an inch an hour below the band, and
will continue to lessen. As the day`s heating continues, am still
expecting a few thunderstorms to be able to develop this afternoon
across the forecast area. However with weak CAPE but a cooler
airmass, could still see small hail falling out from them.
Downward QG vertical velocities along with drying downsloping
pattern will diminish showers and thunderstorms this evening, with
only a slight chance of them remaining in NW flow over the
mountains. There is still thunderstorms in the forecast this
evening, however conditions don`t look very favorable, may strip
these out later.
&&
.SHORT TERM...(Today and tonight)
Issued at 350 AM MDT Fri May 27 2016
The upper level low will track across southeast Colorado and into
western Kansas today. A deformation band has developed on the back
side of the low. This area of rain should shift east with the low
this morning. Lowered pops for the northern half of the Front
Range. Will keep the higher pops south and across the eastern
plains due to the area of rain. Rainfall will be light to moderate
with additional amounts mostly less than a half inch. Most of the
precipitation has remained east of the mountains and is expected
to stay east, so will cancel the Winter Weather Advisory.
Airmass becomes slightly unstable this afternoon, mainly over the
higher terrain and far northeast corner of the state. Will have
scattered showers and thunderstorms in the forecast for this with
higher pops over the eastern plains where the deformation zone is
expected to be.
Rain showers and thunderstorms are expected to decrease late this
afternoon and evening as the airmass stabilizes and the low moves
east of the state. Will have low pops in the for the evening and
then end them most locations after midnight. There may be a few
stray showers over the mountains and far northeast Colorado after
midnight and will keep slight pops in the forecast.
.LONG TERM...(Saturday through Thursday)
Issued at 350 AM MDT Fri May 27 2016
The Memorial Day weekend should start out dry Saturday morning
with a weak mid-level shortwave ridge over the area and a light
west-northwesterly flow spreading drier and warmer air over the
fcst area. by afternoon some of the models show this ridge nosing
up into the Dakotas and a weak shortwave trough on its heels
passing over the CWA during the late afternoon/early evening
hours. Strong solar heating resulting in steep lapse rates and the
lingering presence of low-level moisture should manage to produce
isolated to scattered showers/t-storms over the Front Range mtns
and higher foothills by early afternoon. Destabilization aloft and
additional heating of the boundary layer may be sufficient to
spark a few late afternoon/evening t-storms on the plains and
Palmer Divide. Potential instability and shear do not appear
adequate to produce strong/deep convective updrafts leading to
severe t-storms. Furthermore qpf guidance indicates the bulk of
the precip that day will fall over higher elevations...and most of
that less than a quarter inch. As for Temperatures on
Saturday...model guidance indicates a 10-12deg f warmup for most
areas. That seems reasonable with the warming aloft and with a few
more hours sunshine.
Sunday may begin about the same with morning sunshine and mild
temperatures. however by mid to late morning a tight lee slope
pressure gradient creates gusty south-southeasterly sfc winds on
the plains according to the NAM...GFS and Canadian models which
then drives increasing amounts of low-level moisture up into
east-central and northeast Colorado. Could see isolated to widely
scattered t-storms forming on the plains by mid-afternoon...but
the stronger convection will probably stay east of the CWA as it
now appears. Meanwhile mountain areas should again see another
round of afternoon and early evening showers/t-storms but probably
with the coverage expected on Saturday since there does not appear
to be any forcing mechanism aloft. Sunday temperatures should
continue to rise by another 3-5 deg f for most locales with mid-to-
upper 70s on the plains.
For Memorial day...models are offering mixed signals. The NAM
shows another shortwave trough swinging over the area during the
day and interacting with a moisture rich sely low-level flow
together with bndry layer cyclongensis across the northeast
corner of the state. This would potentially result in a stormy
afternoon and evening for this area. Whereas...the GFS...ECMWF
and Canadian models indicate a drier day for the CWA with a warm
and dry swly flow aloft. I like a blend of the models here since
I`m not sure the boundary layer will dry out as much as the models
indicate as they all generally indicate sely sfc winds on the
plains. Temperatures on Monday about the same or perhaps a deg or
two lower than the day before.
For the period Tuesday-Thursday...models continue to indicate
troughing over the Rocky Mtn Region and as a result a slight dip
in temperatures and a slightly better chance of afternoon and
evening showers/t-storms. The best chance for this activity
appears to be on Tuesday and Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1244 PM MDT Fri May 27 2016
A few weak thunderstorms have formed near KDEN, tracking north to
south. With low freezing levels, even weak thunderstorms will have
the ability to produce small hail. At this time, it looks like TS
should stay east of KBJC and KAPA so will keep it out of their
TAFs. Ceilings are expected to range from 5000 to 6000 feet
through 22z except for near 3000 feet in SHRA/TS, then start
improving through the rest of the afternoon and clear out this
evening. Gusty north to northeasterly winds with gusts to 25
knots possible will decrease after 00z and eventually back toward
drainage. Light winds are expected through 18z Saturday.
&&
.BOU Watches/Warnings/Advisories...
None.
&&
$$
UPDATE...Kriederman
SHORT TERM...Meier
LONG TERM...Baker
AVIATION...Kriederman
[top]
Area Forecast Discussion
National Weather Service Grand Junction CO
312 AM MDT FRI MAY 27 2016
.SHORT TERM...(Today through Saturday)
Issued at 311 AM MDT Fri May 27 2016
A few showers continue this morning due to wraparound flow from
the low that brought the rain and storms yesterday with occasional
snow being reported at the highest elevations. These showers will
weaken as the night progresses but not completely end so you may
see a few raindrops for the morning commute along and south of the
I-70 corridor as well as portions of the San Juans.
While a ridge does build in today, plenty of moisture and daytime
heating will allow another day of showers and storms. Intensity
and coverage will be somewhat less since the area of low pressure, and
forcing it provided, will have shifted well to our east. Like
Thursday, convection should start firing around noon and continue
through sunset with some spotty showers continuing through
midnight.
Flow becomes more zonal Saturday as a weak wave moves over the
region allowing another afternoon and evening of unsettled
weather. Models paint precip over the highest terrain which looks
good as steering winds are quite weak during this timeframe.
Outside of those areas, partly cloudy skies are expected with
temperatures finally reaching more normal values.
.LONG TERM...(Saturday night through Thursday)
Issued at 334 PM MDT Thu May 26 2016
The long wave trough will reload along the west coast during the
weekend as the next low pressure disturbance develops over
southern California. The flow over our area will quickly become
southwest again by Sat. This relatively unstable flow will carry
enough moisture to keep afternoon convection in the
forecast, mainly along the mountains.
Models show this low weakening as it gradually tracks east early
in the work week. Also a stronger low center over the Pacific
northwest will shift east. As both of these features head east,
high pressure will develop along the west coast. So continued
mainly mountain convection can be expected each afternoon through
Tue. Then the west coast ridge will strengthen and move into the
Great Basin for warmer and drier conditions midweek and beyond.
Temperatures are expected to be a tad below normal during the
weekend, then right around normal through the first half of the
work week. Temps will then climb to just a tad above normal by
the end of the period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 311 AM MDT Fri May 27 2016
Mid level clouds continue to hang around this morning with cigs
varying from about 3.5K feet at ASE up to 10K feet at DRO. Cigs
should lift through the morning hours as the low pressure to our
east continues moving in that direction. A few showers will likely
persist though so those TAF sites near and under the showers may see
the lower cigs persist. KASE...KEGE...KTEX...KRIL and KGJT look to
have the best chance for this to occur. vcsh looks safe for those
sites for the next few hours until some clearing occurs. After
18z...more convection is expected though coverage will be less.
Not sold on any one TAF site actually seeing a -tsra on station so
will leave out for now. By 02z...most convection will end though
some stray showers will persist. Even mentioning the convection
and showery precip, still expect mostly vfr conditions today.
&&
.GJT Watches/Warnings/Advisories...
CO...Winter Weather Advisory until 6 AM MDT early this morning for
COZ010-012.
UT...None.
&&
$$
SHORT TERM...TGR
LONG TERM...EH
AVIATION...TGR
Area Forecast Discussion
National Weather Service Pueblo CO
325 PM MDT THU MAY 26 2016
.SHORT TERM...(This evening through Friday)
Issued at 325 PM MDT Thu May 26 2016
...Potential for heavy rain and mountain snows continues into
morning...
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as previously
thought. There certainly could be some enhanced runoff into
fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point.
Should see a pretty good band of rain and higher elevation snow
take shape and move eastward across the plains on Friday as the
upper low pulls eastward with UVV associated with upper level
deformation, along with mid level north to northeast flow
impinging on the eastern mountains. Cooling aloft under the
passing low, with H7 temperatures progged between 0C and 4C across
the area into early tomorrow morning, supports snow levels down
to around 9000 feet before lifting back up to at or above 10K
through the day, with scattered showers and thunderstorms area
wide through the afternoon. Current winter weather highlights
still look good with total snow accumulations of over a foot on
top of Pikes Peak and 2 to 4 inches across the rest of Teller
County, with 4 to locally 8 inches across the higher elevations
of the Sawatch and Mosquito Ranges, and the Sangre de Cristo and
Wet Mountains. The passing system sends a cold front across the
Eastern Plains, with breezy north winds and temps below seasonal
averages expected across the area through the day tomorrow.
.LONG TERM...(Friday night through Thursday)
Issued at 325 PM MDT Thu May 26 2016
Saturday-Sunday...Drier westerly flow aloft across the area Saturday
gives way to increasing southwest flow through the day on Sunday
ahead of an embedded disturbance translating across the southern
Rockies through Sunday night. There will be enough residual moisture
to support isolated to scattered showers and storms across the area
Saturday afternoon and evening, with the best coverage over and near
the higher terrain. There remains some model diffecences on
Sunday, through there looks to be a better chance of showers and
storms expected across the area through the afternoon and
evening, with stronger storms possible across the far SE Plains
with a dry line in the vicinity of western Kansas. Temperatures
look to be at or slightly below seasonal averages through the
weekend.
Monday-Thursday...A relatively cool and unsettled weather pattern
remains in the offing through early next week, as another embedded
disturbance translates across the northern and central Rockies
sends a front across the plains on Monday, with cool upslope flow
persisting across the area on Tuesday. This will keep generally
scattered afternoon and evening showers and storms possible
through the period, with temperatures remaining at or slightly
below seasonal averages.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 325 PM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory until 6 AM MDT Friday for COZ058-060.
Winter Storm Warning until 6 PM MDT Friday for COZ082.
Winter Weather Advisory until noon MDT Friday for COZ073-080.
&&
$$
SHORT TERM...KT/MW
LONG TERM...MW
AVIATION...KT/MW
Area Forecast Discussion
National Weather Service Pueblo CO
1138 AM MDT THU MAY 26 2016
.UPDATE...
Issued at 1023 AM MDT Thu May 26 2016
Models still converging on a farther south position of the cold
front this afternoon which puts more of southeast Colorado under
the threat for severe weather as it lifts back northward. Several
runs now of the HRRR are developing supercell thunderstorms along
the boundary across eastern Las Animas and northern Baca
counties...which track north northeastward through the afternoon.
Pretty good updraft helicity at times with some of these
cells...and they will be in an area of good atmospheric low level helicity
given easterly surface winds beneath southwest flow aloft. Will
have to monitor these for not only a severe thunderstorm
potential...but a tornado potential as well. Other area of concern
will be across El Paso county. Every other run of the HRRR
oscillates between more persistent strong convective regime which
persists through the afternoon...to a scenario of brief severe
convection quickly transitioning over to more stratiform scenario.
Still think there is a window for severe thunderstorm
potential...even an isolated tornado threat through the
afternoon...so forecast leans towards the more convective scenario
for now.
Severe potential will be shifting northward through the afternoon
as the front lifts northward...and may be largely done by 6 PM.
Wrap around spreads in tonight as the upper low slowly moves
eastward across Colorodo. This will put a steady rain/higher
elevation snow across the area...particularly for the Pikes Peak
region. Snow levels down to 9000 feet still look on track as do
highlights across the mountains. Should see a pretty good band of
rain take shape and move eastward across the plains on Friday as
the upper low pulls eastward.
For now...although rainfall could be moderate at times
tonight through Friday...think that rates are not as likely to
exceed flash flood thresholds on the Waldo burn scar as
previously thought. There certainly could be some enhanced runoff
into fountain creek...but this may end up being more steady rises
rather than a sudden one. The only caveat to this is if a strong
to severe cell hits the Waldo Burn scar this afternoon. If this
happens...then there would be a potential for flash flooding...with
greatest threat before 6 PM. Since cells will be hit or miss early
on...no plans to issue any flash flood watches at this point. -KT
&&
.SHORT TERM...(Today and tonight)
Issued at 347 AM MDT Thu May 26 2016
...A POTENTIALLY VERY ACTIVE DAY ACROSS THE FORECAST AREA..
Currently...
Upper closed low which promises to bring active wx to the region
later today and tonight was spinning over nw AZ at 3 am. Over the
immediate area, boundary extended from roughly KSPD to Kim to KPUB
and the banked up along the mtns. North of this boundary winds are
generally east to northeast with dwpts in the 40s...with 50s over
the extreme east. South of this boundary it was much dryer...with
dwpts in the teens and 20s. Low clouds were generally north of
highway 50 mainly in Kiowa county.
Today...
Guidance not in good agreement this morning. shorter range hi res
guidance wants to keep the boundary down towards the Raton Mesa and
moves it only slowly north with time. Other guidance such as the NAM
and GFS move the boundary farther north with time...generally north
of highway 50. The location of this boundary is going to be critical
on where severe thunderstorms develop today. if the boundary remains
farther south...than more of the plains will be under a threat of
severe storms. If the boundary lift north...than less of the region
will be under the threat. As of 3 am...SPC has the svr threat area
mainly north of highway 50. However, as mentioned above...HRRR runs
have been persistent on wanting to keep this boundary down towards
the Raton Mesa, and lifting it north late in the day. Latest runs of
the HRRR does show a few rotating storms on the se Plains later
today.
The next concern for today will be the threat of heavier precip
over the greater Pikes Peak region. All guidance shows heavier
convective precip developing over the Pikes Peak area later this
afternoon, although the guidance has the QPF bullseyes in a variety
of locations. Conceptually...with the closed low moving over the
region and northeasterly 700 mb winds impinging on the Pikes Peak/S
mtn areas, the chance of heavier precip is rather high. The concern
is will the precip fall heavy enough to produce
flooding...especially over the burn scars? Given that the
antecedent conditions are not favorable for flash flooding...I
did not issue any flood hilites for the region, but conditions
will have to be watched closely for the threat of locally heavy
rain over the Waldo burn scar region.
Snow will fall over the highest peaks today. A winter storm warning
is already in effect for Pikes Peak...and have added snow advisories
for the higher elevations of the Wets...N Sangres...and for the C
mtns. The heaviest snow will fall over Pikes Peak.
Tonight...
Severe threat will continue over the far eastern plains, with the
greatest threat along and north of the boundary. Steady precip, with
embedded convection will develop/continue over the greater Pikes
Peak area as strong upslope flow in the lower atmosphere impinges
across this region. it is not out of the question that some areas in
the Pikes Peak area are going to see an inch of liquid...with local
amounts in excess of 2 inches possible. Heavy wet snow will fall
over the highest elevations of both Teller and El Paso counties. I
expect most of the accumulating snow will fall above ~9000 feet.
With the snow levels falling...the threat for flooding over the burn
scar will decrease.
Summarizing...
Severe storms will be possible over the Plains today. The severe
potential will extend includes the I-25 corridor region. I would not
be too surprised if the 1300 UTC SPC DY1 outlook has more of se CO
outlooked for severe weather based on the HRRR output. All severe
convective modes will be possible...with the greatest threat for a
tornado or two along the boundary that will extend across the
Plains. I anticipate a tornado watch will be issued later today for
parts of the plains.
Heavy rains will likely occur across most if not all of the Pikes
Peak region later this afternoon and into tonight. Some convective
heavy rains will likely occur later this afternoon. If one of these
storms develops over the burn scar...than a flash flood threat will
be possible. A flash flood watch may be needed later today for the
burn scar.
heavy snow will fall across the mtns. The heaviest accums will
occur above 9000 feet. The heaviest snow will fall over Pikes Peak.
/Hodanish
.LONG TERM...(Friday through Wednesday)
Issued at 347 AM MDT Thu May 26 2016
...Heavy rain and mountain snows continue Friday morning...
Main concern in the extended will be for Friday morning, as the
upper low tracks straight through southeastern Colorado. Storm looks
fairly dynamic, with h7-h5 flow in the 40-50 Kt range rounding the
low center in the NW quad. Mid level flow will be from the N to
NE...bringing a strong orographic component to the Ern mountain
ranges, and contributing to more widespread moderate to heavy precip
in the 12 through 18Z period Friday. The focus for the heaviest QPF
will be over the southern front range, Wets and Sangres, and the I-
25 corridor. The NAM has another 0.5 inches to inch of precip in
this region Fri morn. Other models not quite as wet, but still in
the 0.25-0.50 inch range. With mid level lapse rates falling rapidly
Fri morning, threat for intense convection will drop, but moderate
steady precip could lead to additional problems for local streams
and poor drainage areas. Snow levels will drop to around 8500-9000
feet Fri morning, then rebound to around 10K feet during the day.
Heavy snow accums likely for Pikes Peak above 11000 feet, and higher
elevations of the West and Sangres. Pikes Peak should see an
additional 4-6 inches Friday, and a couple inches for the other
mountain areas. Total snowfall for Pikes Peak could exceed one
foot. Steady precip will wind down Fri afternoon, but there
should still be widespread showers, particularly over the higher
terrain, through the evening. Temps Friday will be about 15
degrees below average for late May.
After Friday, rest of the forecast period is relatively uneventful,
with daily chances for showers, particularly over the mts, and
temps generally around or slightly below average. Quasi-zonal flow
on Sat will transition to SW flow aloft on Sunday as a weaker low
pressure system begins to move into western CO. This system will
move through late Monday into early Tue, and bring another round of
widespread showers and a few storms to the area. The parent low to
this trough will move through the northern Rockies and High Plains
during the midweek period. The GFS is a bit farther south and
stronger with this system than the ECMWF, and there is a large
ensemble spread by 144 hours and beyond. But it is likely the bulk
of this system will remain to our north. As the trough and
associated cold front passes to the east, the Plains will likely
see another round of showers and storms, some of which could be on
the strong side, in the Tue-Wed time period. Stayed pretty close to
the Blended ensemble-based grids for the latter part of the forecast
period, which progs near to slightly below average temps and low-
sct POPs for the region. Rose
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1133 AM MDT Thu May 26 2016
VFR conditions will transition to to MVFR as thunderstorms develop
over the mountains and spread eastward onto the plains this
afternoon through tonight. Strong to severe thunderstorms will be
possible this afternoon after 20-21z for KCOS and KPUB with
erratic wind gusts to 40 kts or higher along with hail...and heavy
rainfall. Winds will shift from the north after thunderstorms
roll through with gusts to 20-30 kts tonight. There may be a lull
in showers for the KCOS terminal before they increase again after
04z with more widespread MVFR CIGS and VIS due to rainfall. PUB
will see stratiform rain and MVFR conditions spread in after 09z.
Winds will increase again from the north at both KCOS and KPUB
Friday morning.
&&
.PUB Watches/Warnings/Advisories...
Winter Weather Advisory from 3 PM this afternoon to 6 AM MDT
Friday for COZ058-060.
Winter Storm Warning from 3 PM this afternoon to 6 PM MDT Friday
for COZ082.
Winter Weather Advisory from 3 PM this afternoon to noon MDT
Friday for COZ073-080.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...ROSE
AVIATION...KT