Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/27/17

Area Forecast Discussion

National Weather Service Wakefield VA

 824 PM EDT Sat Aug 26 2017

.SYNOPSIS...
Strong high pressure builds east into New England through
Sunday. Low pressure lifts northeast along a stalled coastal
boundary Sunday through Monday. A stronger low lifts northeast
along the Mid Atlantic coast late Monday and Monday night then
pushes out to sea Tuesday.

&&

.NEAR TERM /THROUGH SUNDAY/...
Latest weather analysis reveals 1026+mb surface high pressure
over Ontario into the Great Lakes and the interior northeast. To
the south, a weak stationary boundary is lingering along the
southeast coast, with a surface low lifting along the boundary
from north-central Florida toward the FL/GA coastline this
evening. Just inland, a subtle surface trough is noted just east
of the mountains. Clouds and scattered showers from the
afternoon have largely scoured out this evening with loss of
diurnal heating, leaving a partly to mostly clear and pleasantly
mild evening. Time-lagged HRRR and other high-res models still
maintaining chances for some more showers late, and have stuck
with a low PoP (15-25%) overnight along coastal SE VA-NE NC,
while keeping a dry forecast overnight inland. Lows mainly
60-65F inland...65-70F along the coast.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
The stalled frontal boundary to the S drifts a bit closer to the
coast Sun. Combination of that front and sfc hi pres shifting to
ern New Eng will increase the onshore flow and begin to spread
moisture E-W across the FA (mainly Sun night-Mon). Winds at the
coast (esp invof SE VA-NE NC) becoming gusty to 20-30 mph while
conditions slowly become mostly cloudy. Highs Sun in the
u70s-l80s. Lows Sun night from the l-m60s W to the l70s at the
coast. Highs Mon from the l70s NW to around 80F SE.

Continued model differences and low confidence in potential lo
pres tracking NE (off) the SE CONUS coast (Mon night into Tue).
Most of the impacts expected to be invof SE VA-NE NC (PoPs
60-80%)...though will have PoPs 30-60% elsewhere.
Additionally...gusty ENE winds expected (highest at the coast)
but how strong they become uncertain attm. Lows Mon night in the
l-m60s W to the l70s at the coast. Highs Tue in the l70s NW to
around 80F SE.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Low pressure (tropical or sub-tropical) lifts offshore the Mid-
Atlantic coast Tuesday night. The low accelerates northeastward
Wednesday as the upper closed low over the Great Lakes opens
and ejects eastward. Outside of scattered showers and embedded
thunder as the system lifts offshore, the main impacts will
remain along the coast. High surf, rough seas, gale conditions,
and coastal flooding are possible near the coast. Guidance
indicates drying conditions Wednesday as subsidence behind the
system impacts the region, but given the uncertainty, will carry
chance PoPs Wednesday. The weakening upper wave pushes across
the Northeast Thursday as the best moisture pushes offshore.
Will keep mention of slight chance PoPs Thursday as the wave
slides offshore and another upper trough pushes across the Great
Lakes. An associated cold front drops into the region on Friday
as high pressure builds over the Great Lakes Region. Moisture
appears limited along the boundary, so will only mention slight
chance PoPs across the southeast local area Friday. High
pressure builds over the region early in the weekend.

Temperatures will remain on the cool side of normal for late
August/early September, with highs generally in the low to mid 80`s.
Lows generally in the 60`s.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR conditions will continue through the TAF period. Winds will
be NE-E around 10 kt tonight but expected to be gusty to 15-25
kt on Sunday. Some lower clouds may develop during the overnight
(1500-2500 ft) and there may be some scattered ceilings closer
to the coasts. ISOLD SHRAs and/or tstms again possible on
Sunday. A low pressure system moving up the SE coast may impact
the region early during the upcoming week.

&&

.MARINE...
Low pressure organizing along the SE coast this weekend, coupled
with high pressure situated over New England, will be major factors
in marine conditions through the middle of next week. Regardless of
whether the aforementioned low gains tropical status or not, the
pressure gradient between this feature and the high to our north
will likely cause high end SCA to Gale conditions across a large
portion of the marine area. Conditions will begin to deteriorate by
tonight with worsening conditions into Monday and then the worst
conditions expected Tuesday when the strongest winds (gusts 35-40kt)
are expected. Seas build to 8-11 ft by Monday due to persistent
onshore flow and could build further on Tuesday. This forecast is
based on a compromise of the global models showing low pressure
riding up the NC coast Mon night/Tues then shooting farther out to
sea on Wednesday. Waves on the Bay would likely reach 3-6 ft and up
to 7-8 ft at the mouth of the Bay as early as Monday. Currently have
SCAs out for the all waters except the York/Rappahannock/upper James
Rivers that last thru 6pm Monday (4th period) due to high
confidence. May eventually need gale headlines for much of the same
areas on Tuesday (of course that would also be dependent on
coordination with NHC). In addition, nearshore surf heights probably
reach 8 ft Monday/Tuesday and a high surf advisory will likely be
needed.

Plenty of uncertainty still exists in the models with regards to the
marine conditions in the coming days. However, an extended period of
poor conditions does appear likely this weekend into the first of
next week with slowly improving conditions through Wed/Thurs.

Moderate risk of rip currents across our northern beaches
Sunday. High risk of rip currents from VA Beach to the northern
OBX as onshore winds increase and seas build. There will be an
elevated threat of rip currents through the first of next week
due to the coastal low.

&&

.TIDES/COASTAL FLOODING...
A persistent period of onshore flow is expected to develop Sat
and continue into early next week as high pressure becomes
anchored over New England and low pressure develops off the
Southeast Coast. Tidal departures are expected to build to
1.0-1.5 ft above normal later Sun into Mon with localized
departures of 2.0-2.75 ft above normal possible Mon into Tue.
Minor to moderate flooding thresholds may be reached during
times of high tide Mon into Tue.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 6 PM EDT Monday for ANZ632>634-656-
     658.
     Small Craft Advisory from 4 AM Sunday to 6 PM EDT Monday for
     ANZ630-631-638-652-654.
     Small Craft Advisory from 10 AM Sunday to 6 PM EDT Monday for
     ANZ650.

&&

$$
SYNOPSIS...ALB/MPR
NEAR TERM...MAM
SHORT TERM...ALB/MPR/SAM
LONG TERM...JDM/MPR
AVIATION...ALB/JEF
MARINE...JDM
TIDES/COASTAL FLOODING...




Area Forecast Discussion

National Weather Service Bismarck ND

 905 PM CDT Sat Aug 26 2017

.UPDATE...
Issued at 903 PM CDT Sat Aug 26 2017

Convection rapidly trending down this evening. Will end all
precipitation by Midnight. Clearing skies overnight with high
pressure pushing south from Canada.

UPDATE Issued at 620 PM CDT Sat Aug 26 2017

Convection starting to diminish rapidly this evening so have
removed the mention of severe thunderstorms from forecast.
Otherwise there are scattered showers and a few thunderstorms
across the south central. A few showers north. Otherwise the
precipitation will end this evening with partly cloudy to clear
skies overnight. Will monitor for fog but not as likely as last
night.

&&

.SHORT TERM...(This evening through Sunday)
Issued at 233 PM CDT Sat Aug 26 2017

Thunderstorm potential, mainly south and west of the Missouri
River, is the main weather concern through this evening.

As of 19 UTC, weak, elevated convection continues in advance of
a mid-level impulse in northwest flow aloft that`s characterized
by a RAP-analyzed vorticity maximum approaching southwestern ND.
Weak low-level flow is contributing to correspondingly weak mixing
of the lower atmosphere, which is in part helping to maintain an
area of upper 50s to lower 60s F dewpoints across most of western
and central ND. That in turn is yielding MLCAPE of 1500-2000 J/kg.
Effective-layer shear this afternoon and evening is expected to
range from only 20 kt in the Turtle Mountain region (where the
threat of severe storms is thus negligible) to 30 to 40 kt in
western and south central ND. The primary uncertainty with the
convective forecast relates to the coverage of surface-based
storms in the late afternoon and evening due to a combination of
weak low-level convergence, the fact that the primary forcing
aloft tied to the mid-level wave will be focused in western SD by
00 UTC, and potential capping shown in some model soundings. In
regard to the latter concern, soundings from the 12 UTC NAM
suggest MLCIN in excess of -75 J/kg will persist through early
evening, while more recent RAP output suggests MLCIN may be more
minimized in favor of at least a few boundary-layer-based storms,
mainly in far southwestern ND.

While uncertainty in storm coverage continues, we have to note
that trends in the most recent HRRR and ESRL-HRRR runs reversed
their prior course of a muted event and instead are starting to
favor a severe risk centered on the Hettinger, Mott, and Elgin
areas in the 21-00 UTC time frame. Given those trends, we chose
to continue explicitly mentioning a risk of severe storms in the
gridded and point-and-click forecasts across all of southwest and
into Grant and Sioux Counties in far south central ND through the
early evening. Weak low-level wind fields and deep west-northwest
flow above 700 mb will yield elongated straight-line hodographs
in favor of splitting storms and multicell clusters, but the CAPE
and shear setting, mid-level lapse rates around 7 C/km, and
sounding analog matching techniques all favor a severe hail and
wind risk with any established storms. We will continue
advertising hail up to the size of half dollars and wind gusts up
to 60 mph as the primary hazards, though again, storm coverage is
uncertain and if anything we may end up with only one or two
severe storms before the main event becomes established further
south in SD.

Otherwise, a surface high is expected to shift southward into the
area tonight and Sunday. We leaned on the cooler edge of guidance
for lows tonight given the proximity of the surface ridge, with
forecast lows from the upper 40s to lower 50s F. Patchy fog may
form given light winds and minimal low-level turbulence, but we
refrained from adding it to the forecast at this time since not
much support exists for its formation in deterministic high-
resolution guidance. Highs by Sunday afternoon are forecast to
range from the upper 70s F in the James River valley to the mid
80s F in western ND.

.LONG TERM...(Sunday night through Saturday)
Issued at 233 PM CDT Sat Aug 26 2017

Warm and mainly dry weather is forecast next week under the
influence of a 500 mb ridge that is forecast to amplify out of the
western U.S. and into the northern Plains. The 00 and 12 UTC GFS
and ECMWF and their ensembles support widespread highs in the 80s
to lower 90s F, with the warmest days possibly coming Tuesday and
Friday. A lee surface trough will likely be present in eastern MT
during this period, and could offer a non-zero risk of convection
depending on low-level moisture return, but in the probability of
precipitation will generally be low until the ridge flattens late
in the week.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 620 PM CDT Sat Aug 26 2017

Surface trough over central North Dakota will move east tonight
as high pressure builds into the region Sunday. VFR all TAFs
through the 00Z TAFs.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...WAA
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...WAA




Area Forecast Discussion

National Weather Service Hastings NE

 649 PM CDT Sat Aug 26 2017

.SHORT TERM...(This evening through Sunday)
Issued at 254 PM CDT Sat Aug 26 2017

A weak frontal boundary extending from central Nebraska and
across the NE/KS state lines this afternoon has provided the focus
for some isolated shower and thunderstorm activity the past few
hours across our far western counties. Instability initially was
limited to this area as extensive cloud cover persisted across
the heart of the local area until around noon. With this cloud
cover now gone and temperatures climbing into the lower to middle
80s the past few hours...mesoanalysis indicates we have about
3000 Joules of ML CAPE to work with if storms are able to develop.
That said...there still remains a fairly robust CAP in place
across the region...and some forcing will be needed to get
thunderstorms going.

As a result...confidence in forecast for the remainder of the
afternoon and evening is on the lower side...as storm development
will be primarily diurnally or outflow driven and likely near the
aforementioned boundary. That said...if additional storms do
initiate...expect the possibility for some large hail and strong
thunderstorm wind gusts thanks to the large CAPE values...so kept
this mention in the afternoon update of the hazardous weather
outlook.

Late this evening...several of the models are picking up on an
upper level disturbance across eastern Montana racing south across
the local area by the early morning hours Sunday. This disturbance
should help provide enough forcing for scattered thunderstorm
activity spreading from north to south early Sunday morning. While
exact coverage is hard to pinpoint...there appears at least a
fairly good shot for precipitation for a large portion of the area
from the early morning through early afternoon hours tomorrow.
Depending on how much cloud cover we hang on to tomorrow
afternoon...temperatures will generally range from the mid 70s to
mid 80s...and lowered highs several degrees to reflect
this...keeping actual forecast values just on the warmer side of
guidance.

.LONG TERM...(Sunday night through Saturday)
Issued at 254 PM CDT Sat Aug 26 2017

High pressure across the Great Basin coupled with low pressure
across the Great Lakes Region will result in northerly upper level
flow across the local area through the end of next week. With
no significant disturbances in this flow...expect a dry week
across the local area with near to slightly below normal
temperatures each day.

Expect the upper level ridge to our west to eventually break down
late in the week...with an upper level disturbance possibly
racing across the local area next Friday night. Not
surprisingly...the blended model guidance introduced a small
chance for thunderstorms next Friday night...and given the fact
the ridge to our west will be breaking down about that time...saw
no reason to disagree with this small chance just yet.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday)
Issued at 644 PM CDT Sat Aug 26 2017

It continues to appear dry in the short term, the next several
hours. Some forecast models like the HRRR are bringing at least
scattered thunderstorms into the region later tonight. The HRRR
has been over doing thunderstorms the last few days in the this
pattern and other models continue to be less aggressive with
precipitation tonight. Therefore, will only mention vicinity
thunderstorms and can update to include tempo groups or prevailing
conditions if storms do form and threaten KGRI or KEAR later
tonight. The wind will continue to be very light and rather
variable through the night but should take on a more prevailing
northeasterly direction during the day on Sunday.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&

$$

SHORT TERM...Rossi
LONG TERM...Rossi
AVIATION...Wesely




Area Forecast Discussion

National Weather Service Grand Rapids MI

 755 PM EDT Sat Aug 26 2017

LATEST UPDATE...
Aviation

.SYNOPSIS...
Issued at 314 PM EDT Sat Aug 26 2017

High pressure will drift east tonight and Sunday and low pressure
over the upper Midwest will move toward Lake Michigan. Chances for
showers and thunderstorms will increase Sunday night and Monday as
the low moves south across Lake Michigan. Highs will be in the 70s
this week. A cold front late week will bring another chance of
showers and storms and cooler weather.

&&

.SHORT TERM...(This evening through Monday night)
Issued at 314 PM EDT Sat Aug 26 2017

Forecast concerns deal with convective trends Sunday night and
Monday.

The sunny weather we`ve had the last few days will give way to more
cloudiness precipitation as high pressure over Michigan drifts east.
As low pressure over the Dakotas moves to Minnesota and upper trough
over the Canadian Prairies will move southeast. This trough over
time will deepen as it moves to near Chicago late Monday. The sfc
low over Minnesota will track southeast toward southern Lake
Michigan. West Michigan will be on the east side of the track which
will mean a higher chance of seeing rain, vs the west side.

Pops are mostly unchanged in the forecast and we`ll continue with
likely Monday afternoon as that is also when the upper trough will
deepen the most. Boosted chances of thunderstorms given decent
instability with li`s near -4c. Not expecting severe storms given low
shear values aob 20 knots. Rain chances will diminish Monday night.

Meanwhile, tonight, the northwest cwa may see a brief shower. Latest
regional radar shows showers moving across Wisconsin. Latest HRRR
shows rain moving across the cwa tonight, while the 3km NAM dries
things out. Given dry air in place and lower instability overnight,
the NAM looks like the more reasonable solution so we don`t have
pops southeast of a MKG to Clare line.

We`ll see a slow warming trend through the period, but highs will
remain in the 70s. Humidity will return though by Monday as
dewpoints increase to around 60.

.LONG TERM...(Tuesday through Saturday)
Issued at 314 PM EDT Sat Aug 26 2017

We are looking at a somewhat unsettled weather pattern to start the
long term portion of the forecast, then settling down a bit. The
entire period looks to see around average temperatures for this time
of the year.

We will see shower and storm chances continue for Tue before drying
out then on Wed. The upper low diving SE earlier in the week looks
to be due south of the area Tue morning. It will slowly rotate to
the east, before opening up and scooting out on Wed. The cold pool
aloft will combine with sfc dew points in the 60s to provide
instability for a few showers/storms. Short wave ridging building in
on Wed will clear the clouds and rain chances out.

After a brief break, another chance of showers/storms will come down
Wed night and Thu. Yet another Nrn stream wave dives SE toward the
state and brings another cold front through. This looks like it
should exit by mid-afternoon.

A dry and seasonable period is then expected later Thu through most
of Sat for the first part of the long holiday weekend. A fairly
decent ridge will move in the wake of the Thu short wave. We could
see another wave/front approach late Sat. The timing is questionable
this far out, and we will go with the idea this will be beyond the
long term for now.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 755 PM EDT Sat Aug 26 2017

VFR conditions will continue tonight and Sunday. Considerable
cloudiness will be present, but cigs will be mostly above 8000 ft.
A few light showers/sprinkles (or virga) are possible, but no
significant vsby reductions from are expected.

&&

.MARINE...
Issued at 314 PM EDT Sat Aug 26 2017

South to southeast winds 10 to 20 knots will create waves 1-3/2-4
feet during the next few days.


&&

.HYDROLOGY...
Issued at 154 PM EDT Sat Aug 26 2017

Rainfall amounts through midweek will be around a half inch basin
average. Excessive rainfall looks unlikely for the foreseeable
future given the current pattern that is keeping deep atmospheric
moisture south of the region.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&

$$

SYNOPSIS...04
SHORT TERM...04
LONG TERM...NJJ
AVIATION...Meade
HYDROLOGY...CAS
MARINE...04




Area Forecast Discussion

National Weather Service Memphis TN

 925 PM CDT Sat Aug 26 2017

.UPDATE...

A few light showers are ongoing across the region this evening,
and this activity is likely to continue into the night,
particularly across north Mississippi. Have thus slightly expanded
the areal extent of the slight POPs to encompass areas currently
with shower activity. Temperatures are on track for lows in the
70s overnight. The rest of the forecast is on track at this time.

ZDM

&&

.PREV DISCUSSION... /issued 314 PM CDT Sat Aug 26 2017/

DISCUSSION...Surface analysis this afternoon places Tropical
Storm Harvey between Corpus Christi and San Antonio Texas. A ridge
of high pressure is located over the Great Lakes Region while a
weak inverted surface trough is located over the Lower
Mississippi Valley. As of 3 PM CDT, temperatures across the Mid-
South are in the lower to middle 80s at most locations.

Not much change is expected across the Mid-South as Tropical Storm
Harvey will remain across Southern Texas between Corpus Christi
and San Antonio. The HRRR indicates a potential for some light
rain showers late tonight into perhaps Sunday morning especially across
areas along and south of I-40 as an inverted surface trough will
remain present across the forecast area.

Short term models indicate shower and thunderstorm chances will
gradually increase somewhat for Monday and Tuesday as an an upper
level trough axis moves into portions of the Lower Mississippi
and Tennessee Valleys. A weak cold front is expected to drop into
the region with only isolated to perhaps scattered coverage
expected at this time.

Long term models continue to struggle with the future remnants of
Tropical Storm Harvey. Nonetheless, the trends suggest the
remnants will remain mainly west over portions of Texas up towards
the Red River Valley. It appears the Lower Mississippi Valley
will be on the eastern periphery of this moisture and confidence
for any tropical impacts are too low to continue mention in the
hazardous weather outlook for the time being. Isolated to perhaps
scattered showers and thunderstorms will be possible for the
remainder of the week into next weekend with temperatures
remaining in the 80s for highs and 60s to lower 70s for lows.

CJC

&&

.AVIATION...
00Z TAFs

A continual stream of mid-level clouds (FL100-150) from the
remnants of Hurricane Harvey will continue over the Midsouth
through the next 24 hours. Low level moisture will be sufficient
for scattered to broken daytime cumulus. Isolated daytime showers
from the overlying midlevel clouds, with VFR otherwise prevailing.

PWB

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&

$$




Area Forecast Discussion

National Weather Service Omaha/Valley NE

 610 PM CDT Sat Aug 26 2017

.SHORT TERM...(Tonight through Tuesday)
Issued at 326 PM CDT Sat Aug 26 2017

The chance for thunderstorms tonight, lingering into Sunday, remains
the primary forecast concern.

Surface cold front was analyzed from near Wayne to Columbus across
northeast Nebraska at early afternoon, with another trough/wind
shift just ahead of it into southeast Nebraska. Both features were
settling slowly south through mid afternoon. Low level moisture had
returned to the area as dew points in the upper 60s to near 70 were
noted near and south of frontal zone. SPC RAP analysis indicated
MLCAPE values were approaching 2000 J/kg just ahead of the boundary
with decreasing MLCIN. Expect further erosion of inhibition through
the afternoon and evening as surface heating and some cooling aloft
tied to vort lobe rotating southeast around potent shortwave
tracking through Minnesota affects eastern Nebraska and western
Iowa. Low level convergence is relatively weak along front, but
continued cooling aloft should steepen lapse rates enough to allow
even weakly convergent surface flow to pop widely scattered
convection this evening. As mid level flow increases, so to will
effective shear profiles, with values approaching 30kt or so this
evening. Thus any storms that can fire will have at least some
chance to become strong with initial hail threat. A consensus of
short range hi-res model solutions suggest best chance for storms
will exist in corridor from west central Iowa to along I-80 in
Nebraska late afternoon and early evening, with a gradual
progression south by late evening when loss of heating leads to
decrease in potency and coverage.

Meanwhile, another piece of mid level energy is forecast to drop
southeast from the western Dakotas into central and western Nebraska
this evening and overnight. Initial focus will be for convection
west of our area, but eastward expansion into western sections of
northeast Nebraska are possible by mid/late evening, then into
southeast Nebraska overnight. So will introduce or increase precip
chances in those areas tonight through Sunday morning. Chances
should decrease markedly Sunday afternoon across all of our forecast
area with regards to frontal boundary and Dakota shortwave. However
upper low forming in northern Wisconsin from today`s Minnesota
shortwave will spin vorticity lobes through Minnesota and into Iowa
Sunday afternoon and night, which could touch off scattered
afternoon/early evening showers/storms in western Iowa.

Surface high pressure will settle in behind exiting front/low for
later Sunday night and Monday, bringing clearing skies and cool
northerly breezes. Highs Monday will likely remain in the upper 70s
much of our area, with cool low to mid 50s expected overnight. And
we will still be under the influence of surface high on Tuesday with
only weak return flow setting up in central Nebraska at that time.
Highs close to 80 are forecast Tuesday with dew points nudging
toward 60.

.LONG TERM...(Tuesday night through Saturday)
Issued at 326 PM CDT Sat Aug 26 2017

A relatively quiet weather period is still in the forecast for the
rest of next week. Our area should remain in northwest mid level
flow much of the period, sandwiched between ridging in the West and
a mean trough from the Great Lakes toward the Gulf Coast. A
consensus of model output keeps our area dry until the Thursday
night through Saturday period when a shortwave or two may spark
showers or storms. However timing and strength of these shortwaves
is quite difficult this far out, and models are offering a wide
range of both. Thus will maintain a mention of spotty and small
precip chances during that time. One thing that is consistent
between models is the remnants of Harvey should remain south and
east of our area.

Otherwise we are expecting just a slight warming of temperatures
through the week, with highs from near 80 Wednesday to the middle
80s Saturday, and lows in the upper 50s Tuesday night to the middle
60s Friday night.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 607 PM CDT Sat Aug 26 2017

Initial concern is whether storms can develop along a cold front
that stretches from near KLNK/KOMA northeastward. While there is a
20% chance that this could occur in the area, just not confident
that it would occur at the TAF locations. Otherwise, there may be
some MVFR clouds/fog later tonight at these two locations as well
11-14z. Focus shifts to storms that are developing in central SD,
and their movement into our area overnight. This could bring a 20%
chance of storms to KOFK by 03-5z, but again, not confident that
they would reach the TAF site. These storms could eventually
impact KLNK 12-14z, and will have VCTS during that time.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&

$$

SHORT TERM...Dergan
LONG TERM...Dergan
AVIATION...DeWald




Area Forecast Discussion

National Weather Service Pueblo CO

 251 PM MDT Sat Aug 26 2017

.SHORT TERM...(This evening through Sunday)
Issued at 239 PM MDT Sat Aug 26 2017

Currently...

Isolated thunderstorms were noted over the southern sections of the
Palmer Divide at 2 pm. These isold storms were associated with a
weak wave moving down across the plains at this time. Other isold to
sctd thunderstorms were noted over the higher terrain, especially
across the sw mtns. Otherwise, skies were nearly clear on the plains
and partly to mostly cloudy in the mtns with temp sin the 80s to
L90s on the plains and mainly 70s valleys.

Remainder of this afternoon into tonight...

HRRR showings best chance of storms will be over the far eastern
plains later this afternoon, and one or two of the storms could be
strong as they move south over the far eastern plains. Otherwise,
only isold -tsra will occur over the remainder of the region. Most
of the activity should be out of the region by the early evening
hours.

For tonight, it is expected to be dry with clear skies. By later
tonight, prefrontal forcing will develop over the plains and sfc
winds will shift to the NW in advance of the frontal boundary.

Tomorrow...

Front will move across the region later tomorrow morning roughly
during the 14-17 UTC time frame. Winds will shift to the north after
fropa and gradually veer as the afternoon progresses becoming
easterly by late in the day. Winds will likely come all the way
around to southerly along the I-25 corridor by late afternoon. As
for precip, plains will likely be too dry for storms, although  cant
rule out an isold storms across N El Paso county and possibly the
extreme se plains. Best chance of storms tomorrow will likely be
across the southern Sangre De Cristo mtns and eastern San Juans.

Although a boundary will come down across the plains tomorrow, max
temps will be similar to todays max temps.

.LONG TERM...(Sunday night through Saturday)
Issued at 239 PM MDT Sat Aug 26 2017

Not much difference in the model and ensemble solutions through
the extended period leading to a higher confidence forecast.

Sunday night through Wednesday...high pressure will dominate the
Great Basin, and stretch east into western Colorado through
Wednesday. This will set up broad northerly flow aloft across much
of Colorado. Showers and thunderstorms are expected to develop
each afternoon over the mountain areas, and move south to
southeast through the evening hours, south into New Mexico by late
night. Models are favoring areas along the Continental Divide,
especially the La Garita and San Juan Ranges through this period.
Locally heavy rainfall, small hail and lightning will be the
primary threats. Further east, more isolated to scattered activity
is expected over the Eastern Mountains, which may spread as far
east as the I-25 corridor during the evening hours before
dissipating. Temperatures will remain warm across the region with
mid 80s to lower 90s each day across the lower elevations.

Thursday through Saturday...the upper pattern shifts by Thursday
as an upper level shortwave passes to the north. This will force
the high pressure to flatten and rebuild west along the west coast
by the weekend. Flow aloft will become more northwesterly and
energy associated with the shortwave passing to the north will
move across Colorado Friday into Saturday. This will likely bring
better chances for showers and thunderstorms to the Plains,
especially on Friday as a cold front brings upslope flow to the
area. Temperatures will remain warm with generally 80s to lower
90s across much of the region.  Mozley

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 239 PM MDT Sat Aug 26 2017

VFR conditions are anticipated during the next 24 hours at all 3 taf
sites; kpub, kals and kcos. Winds will be light tonight with diurnal
flow. Tomorrow, winds will shift to the north in the morning across
the plains and veer to southerly or southeasterly by late in the day
as a boundary moves south down the plains. No precip is anticipated
at the taf sites tomorrow afternoon.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...HODANISH
LONG TERM...MOZLEY
AVIATION...HODANISH