Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/12/18
Area Forecast Discussion
National Weather Service Bismarck ND
850 PM CDT Mon Jun 11 2018
.UPDATE...
Issued at 839 PM CDT Mon Jun 11 2018
Little overall change with this update. The ND ARB Bowman radar
has shown increasing returns across southwest North Dakota over
the past couple hours through 0140 UTC. NDDOT webcams depict rain
reaching the ground, despite the dry low levels. Thus, have
increased PoPs through the remainder of the evening and through
the overnight as rain showers expand east.
UPDATE Issued at 627 PM CDT Mon Jun 11 2018
Maintained a dry forecast for the evening as very dry low levels
reflected by large surface temperature and dewpoint spreads should
prevent the vast majority of precipitation from reaching the
ground from weak radar returns thus far early this evening.
Otherwise, the CAMs through the 22 UTC HRRR continue to favor a
band of rain showers developing across southwest and much of
central North Dakota overnight in association with the arrival of
the shortwave across Montana. Rather weak mid level lapse rates
should be the limiting factor to thunderstorm potential. Still
some uncertainty how much rainfall will be lost initially to
evaporation given the dry low levels.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 326 PM CDT Mon Jun 11 2018
The highlight of the short term forecast is on shower potential
overnight southwest and central.
Afternoon GOES-16 imagery shows a midlevel shortwave trough moving
eastward across central MT, and the 12 UTC global model suite and
convection-allowing models through the 18 UTC HRRR offer a strong
consensus for showers developing in southwest ND by late evening
and expanding into central ND by about 06 UTC in advance of that
wave. Stout low- and midlevel dry advection in the wake of last
night`s shortwave trough passage has yielded surface dewpoints as
low as 30 F in western and south central ND as of mid afternoon,
and upstream trajectories suggest lower tropospheric moistening
will be slow to occur ahead of the next wave. This suggests that
model QPF output could be overzealous tonight despite a burst of
strong synoptic-scale ascent driven by DCVA ahead of the sharp
500 mb height anomaly associated with the shortwave. Accordingly,
forecast soundings reveal large temperature-dewpoint spreads in
the 0-3-km AGL layer even during simulated precipitation tonight,
but given the strong QPF signal and upstream shower activity in
southern MT, we chose to carry PoPs up to 60 percent in parts of
southwest and central ND overnight.
Another fast-moving shortwave trough is expected to cross the area
Tuesday afternoon within broad cyclonic flow aloft. Both the NMM
and ARW cores of the 12 UTC convection-allowing model guidance do
simulate low-topped showers Tuesday afternoon amid steepening low-
and mid-level lapse rates, so we carried a slight chance of them
in the forecast central. Otherwise, a well-mixed boundary layer
will also support breezy west winds by Tuesday afternoon.
.LONG TERM...(Tuesday night through Monday)
Issued at 326 PM CDT Mon Jun 11 2018
Our attention is on the risk of severe thunderstorms from late
Thursday afternoon through Thursday night in advance of a strong
upper-level shortwave trough that`s expected to eject from the
northern Rockies into central Canada by Friday. A surface low is
expected to deepen during the day Thursday and the associated
isallobaric response will assist southerly return flow that will
likely yield afternoon dewpoints solidly in the middle 60s F per
the 09 UTC SREF and 12 UTC ECMWF solutions. Both the 12 UTC GFS
and NAM suggest higher dewpoints -- in the lower to mid 70s F on
the GFS -- but both model cores, and in particular the GFS, have
had a distinct high bias with surface dewpoints in recent events,
likely due to an overestimation of evapotranspiration that could
in part be resulting from a delayed growing season following the
cold spring. Thus, some of the higher-end parameter space being
offered by the GFS and NAM solutions may not be reachable, but
even the lower-dewpoint solutions support strong instability with
MLCAPE on the order of 3000 J/kg. Strengthening southwest flow
aloft will likely yield a supercell-favorable wind profile, and
greater height falls could aid upscale growth into an eastward-
moving MCS by Thursday night. However, one potential failure mode
with this scenario could be mid-level capping as global models
have consistently advertised a strong inversion at the base of a
formidable elevated mixed layer in the pre-frontal regime,
especially in the south.
Thereafter, southwest flow is expected to persist aloft through
the upcoming weekend, but the primary surface frontal zone with
its richer boundary layer moisture and associated bouyancy may
sink southward into the central Plains. That could result in a
more showery or even stratiform nature to the precipitation by
the weekend if the 12 UTC GFS and ECMWF are correct.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 839 PM CDT Mon Jun 11 2018
Rain showers across southwest North Dakota as of 0140 UTC will
continue to expand into most of central North Dakota through the
late evening and overnight. Rain showers may continue across the James
River Valley through 14-15 UTC Tuesday. A breezy Tuesday is
expected with westerly wind gusts of 25-30kts across western and
much of central North Dakota. VFR conditions expected for the 00
UTC TAF period.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PA
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...PA
Area Forecast Discussion
National Weather Service Columbia SC
737 PM EDT Mon Jun 11 2018
.SYNOPSIS...
An upper trough will remain over the eastern states through
Thursday. A back door front will slip slowly south into the
region tonight and stall over the CSRA and southern Midlands
Tuesday. The front will gradually become diffuse Wednesday. Our
region will remain between an upper ridge to our west, and an
upper low to our east, late this week into early next week.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
This evening, outflow boundaries and abundant low level
moisture will support areas of thunderstorms. Convection may be
enhanced with an h7 shortwave trough in the area. The chance of
thunderstorms will continue through tonight because of
convergence along a backdoor front pushing into the area from
the north. There is uncertainty with the coverage later tonight
because much of the instability may get released by previous
convection.
Steep low-level lapse rates will support strong downburst winds
in the stronger cells. There may also be hail with considerable
convective instability in the hail growth region. Cloudiness
and mixing along the front favors the higher temperature
guidance for tonight.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Weak upper troughiness will remain along the E CONUS. A moist
atmosphere will remain in place. The back door front is expected
to slip south and set up along the CSRA and S Midlands by
afternoon and stall. This is expected to be the main focusing
mechanism for convection. Moderate instability, steep mid-
level lapse rates and a predominant surface boundary support a
chance of severe weather in the southern FA. LI values around -6
suggest stronger cells may be capable of producing damaging
downburst winds and large hail. Shear values remain weak which
limits the threat of organized thunderstorms. Cooler, drier air
and mostly cloudy skies are expected to reduce convective
coverage to the north of the front.
Little overall change Wednesday. Nearly stationary surface
boundary may gradually become diffuse. A moist atmosphere to
remain over the region. Scattered diurnal thunderstorms
expected.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
Little change expected Thursday. Upper trough energy and a
moist atmosphere expected to promote at least scattered diurnal
thunderstorms. From Friday into early next week, the latest GFS
and EC indicate an upper ridge to develop to our west over the
Mississippi and Ohio valleys, with upper trough offshore the
east coast, with upper energy possibly cutting off the Mid
Atlantic coast. Some uncertainties regarding timing of upper
disturbances passing through from the north. Also some
questions on extent of atmospheric moisture, with some
indications of drier air possibly filtering into the region late
in the forecast period. Went with model blend.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Afternoon convection has generally shifted away from the
terminals this evening with only some light rain prevailing at
AGS/DNL to start the forecast period. However, colliding outflow
boundaries are occurring near Columbia and kicking off new
convection as the HRRR depicted so will include VCTS at CAE/CUB
from 00z-02z with tempo lower restrictions in vsbys due to
storms.
Otherwise, expect convection to wind down by midnight as a weak
backdoor front slides south through the area later tonight
shifting winds to the north-northeast around 5 to 8 knots as it
passes. Low clouds expected to arrive behind the front with
MVFR/IFR cigs spreading southward across the region reaching
CAE/CUB/OGB by 04-06z and AGS/DNL by 08z-11z. Could see some
MVFR vsbys due to fog at AGS/OGB ahead of the front with light
winds but some uncertainty due to debris clouds from afternoon
convection. Expect some improvement through the afternoon with
diurnal heating.
EXTENDED AVIATION OUTLOOK...There may be restrictions in
stratus and fog during the early morning hours and also in
mainly afternoon and evening thunderstorms.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service Des Moines IA
643 PM CDT Mon Jun 11 2018
.SHORT TERM.../Tonight through Tuesday/
Issued at 336 PM CDT Mon Jun 11 2018
Strong to severe thunderstorm development along with very heavy
rain were the main focus of the forecast today into this evening
across the western portion of the CWA. Leaned toward a blend of
the latest HRRR/ESRL HRRR and RAP for timing of convection into
the western edges of the CWA this afternoon into tonight.
A warm front extended south-southeast from a surface low in
southeast SD before extending more eastern over far southern Iowa
with a sharp cold front cutting south across eastern Nebraska into
Kansas will be the focus of severe weather later today. A few
storms continue to fester along the warm front from around
Atlantic to Winterset, but remain sub-severe attm.
In the warm sector over southwest to western Iowa, very moist and
unstable atmosphere as surface temps in the lower 90s and surface
dew points in the lower 70s across this area. OAX 19z observed
special sounding indicating a classic loaded gun sounding with a
decent hodograph suggestion plenty of speed and direction shear in
the lower levels. LCL heights range from around 500-1000m, steep
low to mid-level lapse rates, very high surface based CAPE, and
significant effective helicity ranging as high as 200 m2/s2 along
and southwest of the warm front in southern Iowa. The helicity,
along with high sigtor and supercell parameters, increases
through the rest of the afternoon.
Timing of severe convection into the CWA looks to be late in the
day, more likely past 22z to 23z in the far west to southwest and
possibly even later. Only concern is if current weak convection
along the warm front releases an outflow boundary providing
another trigger mechanism for storms to develop. The instability
gradient follows along with the warm front orientation and any
storms that develop are likely to follow this gradient into the
southern portions of Iowa. Certainly concerned with the tornadic
threat over the far west-central to southwest Iowa as well as the
large hail and damaging wind threat through around 02-03z, but
storms are anticipated to persist into the late evening. The other
potential is very heavy rain with warm layer cloud depths topping
out over 14kft and precipitable water values over 1.50 inches and
weak Corfidi vectors nearly lined up with the storm motion
tonight. Certainly some training is possible late tonight into the
overnight hours as well as the very efficient rain producers
leading to the potential for flash flooding.
.LONG TERM.../Tuesday night through Monday/
Issued at 336 PM CDT Mon Jun 11 2018
Wednesday night into Thursday, a quick moving shortwave will bring
another round of storms with heavy rain by the early morning hours
Thursday. Certainly looking better potential for heavy rain event
that severe weather potential with the timing of the convection
into the CWA.
Otherwise, the main focus of the extended period was on the hot
and humid weather conditions late this week into the weekend. No
significant change to the ongoing forecast with only a minor tweak
to the maximum temperatures on Friday. With the recent rainfall
and the crops likely in becoming fully mature, the added low level
moisture into the atmosphere is concerning for the heat index
values Friday through Sunday. Each day, heat index values top out
over 100 degrees.
&&
.AVIATION.../For the 00Z TAFS through 00Z Tuesday evening/
Issued at 644 PM CDT Mon Jun 11 2018
Main aviation concern will be with front moving across the state
with widespread convection this evening. Will see restrictions to
both ceilings and visibilities in and around the thunderstorms
with general MVFR ceilings across much of the area otherwise. Will
continue to see MVFR to IFR ceilings late tonight into Tuesday
morning before some improvement by afternoon as drier air enters
the state from the northwest.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Podrazik
LONG TERM...Podrazik
AVIATION...Cogil
Area Forecast Discussion
National Weather Service Quad Cities IA IL
839 PM CDT Mon Jun 11 2018
.UPDATE...
Issued at 827 PM CDT Mon Jun 11 2018
Low level easterly flow continues off the Great Lakes with the
RAP delaying the initiation of precipitation tonight.
The scenario the RAP has been reasonably consistent with is
nocturnal convection initiating in a WAA band along an elevated
front. Initially the RAP had this convection developing across
central Illinois and back building into eastern Iowa. However,
recent runs of the RAP now develops the convection in eastern
Iowa and builds to the southeast into central Illinois.
At the same time, a narrow band of convection has initiated in a
theta e gradient along I-35 and is moving east ahead of the severe
storms in western Iowa. However, radar trends indicate this band
is decaying as it mets drier air.
So, have revised the forecast to have nearly all of the area
remaining dry up through midnight. Isolated to scattered
convection should be seen after midnight but areal coverage may be
lower than forecast.
&&
.SYNOPSIS...
Issued at 238 PM CDT Mon Jun 11 2018
A band of thunderstorms developed during the afternoon hours
across far northeast Missouri and southeast Iowa. The storms were
producing heavy rainfall and frequent lightning. Elsewhere, the
sky remained mostly cloudy through the early afternoon, which
helped hold temperatures down in the 70s at most locations.
&&
.SHORT TERM...(This Evening through Tuesday)
ISSUED AT 238 PM CDT Mon Jun 11 2018
The main forecast issue is thunderstorm trends and coverage. In
the near term, storms in the far south may produce some small
hail, but the severe risk is low. Will continue to monitor the
flash flood threat, but that area has been quite dry and missed
out on the very heavy rain over the past several days.
Later tonight, thunderstorm coverage is not expected to be very
high. The southwest again looks most favored, with potential for a
decaying complex dropping southeast along the instability
gradient. Again, the severe risk is low. For Tuesday, a few
additional non- severe storms are possible. Expect a warm and
muggy day Tuesday, with highs in the 80s. Drier air will be slow
to move in behind the exiting front.
.LONG TERM...(Tuesday Night through Monday)
ISSUED AT 238 PM CDT Mon Jun 11 2018
The main issues in the long term period are increasing heat and
humidity late week, along with more chances for thunderstorms.
Tuesday night and Wednesday will be dry with near to slightly
above normal temps. At least chance pops continue for every period
Wednesday night through Saturday, as several impulses undercut the
upper ridge. There will likely be some stormy periods, but plenty
of dry weather as well. Overall, areas of heavy rain will likely
be the main issue, although cannot rule out some severe storms.
For Friday into next Monday, expect an extended period of high
heat and humidity, with highs mainly in the 90s and heat index
values likely topping 100 degrees, especially south of Interstate
80. Heat advisories and possibly warnings may be needed
eventually.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
ISSUED AT 644 PM CDT Mon Jun 11 2018
MVFR/VFR conditions were across eastern Iowa and northern
Illinois as flow remains off Lake Michigan. Through 06z/12
MVFR/VFR conditions will continue across the area. After 06z/12
some models are suggesting a band of SHRA/TSRA developing across
Illinois and developing northwest into eastern Iowa. Each run
delays the start but the scenario continues. Thus after 06z/12
conditions will deteriorate to MVFR/IFR with the possibility of
TSRA. After 16z/12 conditions improve to MVFR as a cold front
sweep through the area.
&&
.HYDROLOGY...
Issued at 1247 PM CDT Mon Jun 11 2018
With increased confidence of surpassing flood stage, issued flood
warning for the Wapsi at Anamosa. DeWitt is also forecast to rise
above flood stage later this week, but confidence is still low and
opted to continue flood watch.
Rise continue along other tributaries, mostly notably the Rock and
Cedar rivers. Joslin is above flood stage, while Moline is
forecast to go into flood tonight. Conesville is not forecast to
rise above flood stage for another 72 hours or so, and have
maintained the flood watch there.
Due to the recent heavy rainfall, the Mississippi River is also
on the rise. Portions of the river at and downstream from the
Quad Cities may go into action stage later this week. Therefore,
those with interests along the river should monitor river levels.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...RP Kinney
SHORT TERM...RP Kinney
LONG TERM...RP Kinney
AVIATION...08
HYDROLOGY...RP Kinney
Area Forecast Discussion
National Weather Service Hastings NE
642 PM CDT Mon Jun 11 2018
.SHORT TERM...(This evening through Tuesday)
Issued at 310 PM CDT Mon Jun 11 2018
The main concern is in the very short term as the surface cold
front moves southeast across the remainder of the area. The front
is a little slower than originally thought, just making it through
York southwest to Superior, NE and then Osborne, KS. Instability
on the warm side of this front is plentiful with around 3000 J/KG.
Shear is also abundant about 40kts. CIN is becoming negligible as
of this issuance and thus the continued convergence along this
front will allow thunderstorms to quickly develop. Do think the
Nebraska Highway 81 corridor and then Jewell and Mitchell counties
are in the greatest threat for thunderstorms. Think these storms
will develop along the front and move eastward into eastern
Nebraska and northeast Kansas. The main window for thunderstorms
in the forecast area (York/Fillmore/Thayer/Mitchell/Jewell
counties) is the next few hours (3pm - 6pm). After this initial
development, and after the storms move eastward the remainder of
the night will be quiet.
Tonight temperatures are expected in the mid to upper 50s under
mostly clear skies and light northerly winds. Wind are expected to
be light and remain northerly during the day Tuesday. While cooler
the weekend, highs are still expected to be in the mid 80s to low
90s tomorrow...and likely the coolest day of the forecast.
Thunderstorms are possible Tuesday night as an upper disturbance
moves into the central Plains. The best chances will be for Kansas
and especially central and southern Kansas with a small chance for
north central Kansas.
.LONG TERM...(Wednesday through Monday)
Issued at 310 PM CDT Mon Jun 11 2018
Surface high pressure will move off to the east on Wednesday with
southerly flow returning. The bigger deal though is that upper
level ridging will be building with the main wave quite amplified.
Temperatures will only get hotter and hotter throughout the
remainder of the work week and weekend. Highs in the 90s and and
even low 100s. Heat indices will be approaching or exceeding 100,
especially in north central Kansas and SW sections of the forecast
area.
There will be various chances for thunderstorms off and on
throughout the forecast period, especially Wednesday and again
when a front moves through at the end of the forecast. There are
discrepancies in the timing of the frontal passage, so that may
very well change.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Tuesday)
Issued at 637 PM CDT Mon Jun 11 2018
Front has swept through the area, with gusty north winds
prevailing currently. Expect winds to decrease over the next few
hours, becoming light and variable overnight.
With light and variable winds and clear skies, HRRR and RAP are
trying to develop some fog in portions of the area. Confidence
isn`t high, so just included some 6SM BR in the TAFs for now.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Billings Wright
LONG TERM...Billings Wright
AVIATION...Mangels
Area Forecast Discussion
National Weather Service Grand Junction CO
533 PM MDT Mon Jun 11 2018
.SHORT TERM...(Tonight through Tuesday night)
Issued at 353 PM MDT Mon Jun 11 2018
Today is a calmer day in the wind and heat department compared to
the last few days, with our CWA between high pressure to the south
and low pressure to the north. This is allowing for a westerly
flow aloft, which is transporting smoke from existing fires across
southwest Colorado and eastern Utah to the east. Winds will remain
breezy at times this afternoon largely within the 20 to 25 mph
range. Conditions remain hazy in the Grand Valley this afternoon
due to wildfire smoke from the Trail Mountain Wildfire southwest
of Price, Utah. The experimental HRRR smoke model indicates this
smoke reaching the Grand Valley late this afternoon and evening
and spreading east across the I-70 corridor towards Vail overnight
by Tuesday morning. It will generally be hazy so included patchy
smoke in the forecast through noon Tuesday. Regarding the smoke
from the 416 and Burro Wildfires over the SW San Juans, this smoke
is moving quickly to the east this afternoon. Expecting this
smoke to once again drift southward this evening as downsloping
winds take smoke into the Animas Valley, including Durango, all
the way to the New Mexico state line. Visibilities are expected to
lower below a quarter mile at times through the overnight hours
into late Tuesday morning, so issued another Dense Smoke Advisory
for the SW San Juans and Animas River Basin from 9 pm this evening
through noon Tuesday.
Temperatures will be right around normal today but will quickly
rebound to about 10 degrees above normal by Tuesday with H7 temps
rising back to 17C to 19C, as high pressure shifts to the
southeast and shifts the prevailing upper level winds to the
southwest. The southwest winds aloft may help push smoke northward
out of the Grand Valley and I-70 corridor Tuesday afternoon as
upslope flow also takes place. However, the close proximity of the
intense fires in SW Colorado should keep smoke in the forecast
with another Dense Smoke Advisory possible Tuesday night as
typical downsloping winds take smoke southward into the southern
valleys once again.
.LONG TERM...(Wednesday through Monday)
Issued at 353 PM MDT Mon Jun 11 2018
Hot and dry conditions will continue Wednesday into Thursday,
with the models, especially the GFS, hinting at moisture slowly
increasing from the southwest as the high shifts further east with
a low pressure trough moving into the Pacific Northwest.
Precipitable Water (PW) values increase to 0.75 inches over
southern Utah by late Wednesday with this moisture moving into
western Colorado by Thursday. Moisture will increase more late
Friday with values of 0.75 and above across much of the area with
values near an inch over the Four Corners. Saturday looks like the
wettest day with PW values above an inch across much of the area.
Embedded disturbances move through the southwest flow Wednesday
through the weekend, acting as a trigger mechanism on any moisture
and instability to generate storms.
Much of the moisture will remain at the mid and high levels
(mainly above 500 mb) until late Friday into Saturday when the low
levels begin to moisten up. What this means is that any storms
that form in the Wednesday to Friday timeframe will be mainly high
based, with dry lightning and gusty outflow winds the primary
concerns. This translates to potential new wildfire starts with
any outflow winds leading to erratic behavior on already existing
fires. Better chances of wetting rains will occur late Friday
into the weekend, as remnants from Hurricane Bud off the Baja
Peninsula get directed northward towards the Four Corners region
and across eastern Utah and western Colorado. The ECMWF is on
board with this latter onset of moisture late Friday into the
weekend as the PacNW trough digs down the west coast with the high
pressure ridge amplified over the central Plains and Midwest,
allowing for a more direct southerly feed of sub-tropical
moisture. The EC wants to hang onto this moisture through Monday,
while the GFS wants to dry things out Sunday into Monday. Models
tend to want to dry things out too quickly so leaning towards the
EC in terms of the moisture hanging around through much of the
weekend.
The long range models look promising for wetter and more unsettled
conditions heading into next week and next month even. Confidence
is medium in this moisture increase, but low on the timing of how
soon we will see wetting rains. Any moisture will be good to
provide some relief from the already dry and hot conditions and
help with any existing or new wildfires, but the unfortunate part
is the dry lightning threat with the initial onset before the
lower atmosphere moistens up by this weekend. Temperatures are
projected to be much cooler this weekend with this moisture
increase, with values near to a few degrees below normal.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 533 PM MDT Mon Jun 11 2018
VFR conditions will prevail at all TAF sites over the next 24
hours. An exception will be at KDRO where smoke from the ongoing
416 Wildfire will once again drift southward overnight.
Visibilities should hover between 3 to 6 SM between 06Z and 17Z
before winds shift after noon. Winds will be light and terrain
driven overnight.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Dense Smoke Advisory from 9 PM this evening to noon MDT Tuesday
for COZ019-022.
UT...None.
&&
$$
SHORT TERM...MDA
LONG TERM...MDA
AVIATION...TGJT
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1037 PM EDT Mon Jun 11 2018
.SYNOPSIS...
A weak cold front is expected to move south across the region
tonight. Behind the front, Tuesday should be relatively cloudy and
not as warm. Typical summerlike conditions will return for Wednesday
through the weekend.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 1030 PM...The backdoor cold front continues to push SWWD
through the NC piedmont and eastern Upstate, and it about to the
I-26 corridor. Instability is starting to wane ahead of the front,
with the SPC mesoanalysis showing about 1000-1500 J/kg of MUCAPE as
of 02z. So while convection continues to fire with the front, it`s
intensity is not as high as earlier. The severe threat should be
about over. Meanwhile, temps are falling across the NW Piedmont with
increasing NE winds. I made some minor tweaks to the temp grids, and
also updated the PoP to reflect latest obs and radar. This didn`t
have much change to the min temps Tuesday morning.
As of 800 PM...A broken line of convection has developed along the
leading edge of a backdoor cold front across the NC Piedmont, from
Boone to Charlotte. The front will likely continue to trigger new
storms as it pushes toward the SW thru the rest of the evening. The
HRRR maximizes this activity along the NC eastern escarpment and the
I-26 corridor of the Upstate late evening thru about 2 AM. I updated
the PoPs with the latest CONSShort, which shows this trend. Severe
threat still should be marginal, with a few pulse storms producing
strong downbursts. Otherwise, only minor tweaks to the grids with
this update.
Once the front pushes through the FA tonight, instability will
become obsolete and sfc high pressure off to the northeast will
build in overnight and into Tuesday, allowing for a wedge front to
be the main weather pattern feature through the rest of the near
term forecast period. Increasing cloud cover tonight is expected to
persist through into Tuesday as the feature settles in, allowing for
overnight temperatures to remain above normal. Temperatures on
Tuesday will be cooler than today, anywhere from 5 to 10 degrees
cooler, with overall light northeast winds prevailing.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As of 130 pm EDT Monday...Thanks to the progressive pattern, weak
sfc ridging nosed swwd into the cwfa will give to a broader w to sw
flow on Wednesday, with developing lee troughing. Weakly cyclonic
flow aloft will aid in diurnal deep convective development, with
coverage possibly becoming numerous in the mountains. Maximum
temperatures should bounce back to around climo. The pattern atop
the SE CONUS is progged to change little through Thursday, featuring
a weak westerly flow aloft and a non-decsript sfc pattern. Outside
of making an upward adjustment to inherited max temps, a pretty
typical mid-June day is expected featuring diurnally enhanced tstms.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 200 pm EDT Monday: Mid level ridging will build across the
area during the middle of the week but westerly flow will remain not
far to the north. The ridging will strengthen over the middle of the
country by next weekend while a low develops just off the mid-
Atlantic region.
Fairly typical early summer conditions are expected as a result of
this pattern. Expect more coverage of diurnally enhanced showers and
thunderstorms for the middle of the week with the coverage being
less Friday through the weekend as the ridge asserts its influence.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
At KCLT and elsewhere: A backdoor cold front has now pushed through
KHKY and KCLT before 00z, and will continue to push southwestward
thru the remaining TAF sites this evening. A broken line of
convection has developed along the front, affecting KHKY and KCLT.
There are a couple of storms behind the front, but overall, expect
an MVFR cloud deck and spotty light showers behind the front. The
high-res guidance generally agrees that storms will continue to
develop in the remaining areas that haven`t had any convection,
namely, KAVL, KGSP, and KGMU. This will be late this evening, mainly
02-06z. A weak CAD wedge will develop behind the front overnight and
persist thru the day on Tuesday. This will result in widespread IFR
to low MVFR cigs, which will lift somewhat in the aftn, but not
likely to scatter out. The clouds will limit heating and
instability, so areas mainly west and south of the TAF sites will
have much chance of showers or storms. KAND will be closest to the
front, and will put a PROB30 for late aftn there. Winds will turn
out of the NE behind the front and persist thru the period, becoming
weaker later on Tuesday. At KAVL, winds will switch to SE by
daybreak Tuesday.
Outlook: More typical summertime diurnal convection is expected to
return Wednesday, as wedge erodes. Periods of showers and
thunderstorms will be possible each day, thereafter, primarily in
the afternoon, along with morning fog in the mountains and near
lakes.
Confidence Table...
02-08Z 08-14Z 14-20Z 20-00Z
KCLT High 88% High 82% High 82% High 95%
KGSP High 94% High 80% High 89% High 91%
KAVL Med 75% Med 76% High 89% High 86%
KHKY High 87% High 83% High 84% High 100%
KGMU High 90% Med 75% High 84% High 85%
KAND High 100% Med 70% High 84% High 92%
The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:
www.weather.gov/gsp/aviation
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...SW
NEAR TERM...ARK/SGL
SHORT TERM...CSH
LONG TERM...SW
AVIATION...ARK
Area Forecast Discussion
National Weather Service Wichita KS
758 PM CDT Mon Jun 11 2018
.MESOSCALE DISCUSSION...
Issued at 756 PM CDT Mon Jun 11 2018
Storms made an attempt in central KS but fairly quickly died from
apparent combo of capping and dry air aloft. Latest run of HRRR
seems to have captured this fairly well, and supports fairly quick
development 0200-0300 UTC in central KS which then spreads/expands
south during the night. This is consistent with the general model
trends throughout the day. Grids have been updated to delay the
onset slightly. Assuming storms do develop, plan is to expand
severe thunderstorm watch south. -Howerton
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 307 PM CDT Mon Jun 11 2018
Tonight:
Main focus is thunderstorm potential. Salient issues include
apparently overly generous initialization of 850MB moisture by
1200 UTC models, generally weak upper flow and impressive push on
cold front across western KS this morning. These all make timing
and location of initiation/onset in the forecast area challenging.
Forecast was swayed heavily by combo of afternoon HRRR/RAP
forecasts which suggest storms will ramp up around 0000 UTC and
dive mainly south. Direction appears to be heavily influenced by
cold pool given weak upper flow. Impressive 700-500MB directional
shear suggest some large hail possible early with discrete cells,
with shear decreasing during the event. Storms and precipitation
could linger through daybreak in southeast KS.
Tuesday:
Storms may linger a bit past daybreak Tuesday in southeast KS,
otherwise post frontal/post outflow airmass is expected. Models
seem a bit optimistic with synoptic front across the state during
the day. Assuming storms develop as anticipated tonight, seems
more likely that the effective front will be in OK, with a much
slower return to the north. This would push best chance for
precipitation much later Tuesday night, potentially close to
daybreak Wednesday. Obviously boundary location will impact
temperatures and heat indices as well.
Wednesday-Thursday:
Potential for extensive clouds/precipitation Wednesday, especially
early in the day. This makes maxes Wednesday a bit challenging.
Otherwise, drier and warmer airmass anticipated on Thursday.
Nudged initialization maxes up a bit based on 1000-850mb
thicknesses, and winds up a bit given surface pressure gradient
and 850MB flow. -Howerton
.LONG TERM...(Friday through Monday)
Issued at 307 PM CDT Mon Jun 11 2018
Increased temperatures/winds slightly on Friday, as per Thursday
forecast. Otherwise dry and relatively warm. While a rogue storm
or two is possible at peak heating, chances of storms too low to
mention for most of this period. Upper ridge axis drifts east and
builds, so only minor changes in heights is forecast. There is
some consensus for small storm chances in northern sections with
approaching front on Monday. -Howerton
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 533 PM CDT Mon Jun 11 2018
A frontal system will be moving through the region this evening.
Showers and thunderstorms, some severe storms are possible and
are likely to affect all terminals at some point during the hear
TAF period. Only RSL is not expected to have thunderstorm activity
this evening. Once the thunderstorms pass, there may be some
residual rain for a few hours but VFR conditions will quickly
return. VFR conditions are also expected to dominate during the
day tomorrow for all terminals.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 73 94 71 90 / 30 10 40 40
Hutchinson 69 93 68 89 / 30 10 50 40
Newton 70 92 68 88 / 40 10 50 40
ElDorado 70 91 69 87 / 30 10 40 40
Winfield-KWLD 69 94 71 89 / 10 10 40 40
Russell 62 92 65 91 / 10 10 50 20
Great Bend 62 92 66 90 / 10 10 50 20
Salina 67 93 67 90 / 30 10 50 30
McPherson 68 93 67 89 / 30 10 50 30
Coffeyville 67 93 72 89 / 40 20 30 50
Chanute 67 92 70 87 / 50 10 40 50
Iola 67 91 70 86 / 40 10 40 50
Parsons-KPPF 67 93 71 88 / 40 10 40 50
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
MESOSCALE...PJH
SHORT TERM...PJH
LONG TERM...PJH
AVIATION...ELM
Area Forecast Discussion
National Weather Service Louisville KY
825 PM EDT Mon Jun 11 2018
.Forecast Update...
Issued at 825 PM EDT Mon Jun 11 2018
Most of the region has been worked over by the areas of peak
heating. Exception is around KBWG, where a new complex of storms
just south of the KY/TN border is slowly creeping towards. Will be
watching for any new development, but think most of the severe
threat is over for the evening hours. The storm threat is not
though. Airmass is still fairly juicy, and with colliding boundaries
and an effective warm front running from near OWB to near BWG,
expect the chance for storms to continue through the night. Best
chances overnight, based on latest HRRR and NAM, run in the
HNB/SDF/LEX corridor.
Issued at 550 PM EDT Mon Jun 11 2018
Strong to severe storms look likely through the evening. Storms
crossing portion of central and east central KY early this evening
have produced damaging winds and hail up to nickel size. Expect
storms to continue to develop over portions of west central and
south central KY along a boundary extending SE from the Owensboro,
KY area. Plenty of CAPE and DCAPE exist along and south of this
boundary so the strongest storms will continue to pose a damaging
wind threat. Small hail, very heavy rainfall, dangerous cloud to
ground lightning may also accompany storms. Some areas near the
aforementioned boundary may receive repeated storms this evening and
localized flooding may become a threat. Stay tuned to the latest
forecast updates for more information.
&&
.Short Term...(This evening through Tuesday)
Issued at 330 PM EDT Mon Jun 11 2018
(Tonight - Tuesday) - Shower and Thunderstorm chances remain.
Elevated flow continues to be weak. Precipitable water levels across
central Kentucky will stay above 1.5", and in Southern Indiana and
along the Ohio River, precipitable water levels could go over 2".
The muggy damp air is in place, but with the weak shear in place,
organized severe weather isn`t expected. Instability is moderate, so
it won`t take much to initiate showers and thunderstorms. Boundary
interaction and subtle outflow boundaries will likely be the cause
of any shower or storm.
Localized minor flooding will be the greatest threat through Tuesday
night. Areas that see multiple rounds or high rates of rain could
see localized flooding. An expanded flood watch was being considered
as the threat of rain continues, but with a lack of current shower
activity and low confidence, current thinking is a flood watch will
not be needed.
Lightning and wind are always a threat with thunderstorms
precautions should be taken for safety if storms are near.
.Long Term...(Tuesday night through Monday)
Issued at 322 PM EDT Mon Jun 11 2018
Tuesday Night - Wednesday...
A weak cold front trailing from a Canadian system will push into the
region, with another round of showers and storms ahead of it on
Tuesday night. By Wednesday morning, the front will stall near the
area or just east. Could see some redevelopment along this boundary
mainly across our south and east, but expect southern IN to mostly
stay dry by Wednesday. May still carry a 20 pop as the ECMWF has not
come into line with the other model consensus for dry. Not much of a
temperature change behind the boundary, so look for the upper 80s
for highs.
Wednesday Night - Thursday...
Dry NW flow aloft and surface high pressure build in for this time
frame. Should see a dry stretch of weather with lows in the upper
60s, and highs around 85 to 90.
Thursday Night - Monday...
Upper ridge axis originating from the southern Plains will steadily
move into our region and center near the area over the weekend. This
should generally lead to a hotter/drier forecast, although cannot
rule out a few diurnally driven showers and storms each
afternoon/evening. Much will depend on how strong of a subsidence
inversion develops beneath this upper ridge. Look for highs in the
upper 80s to around 90 each day, with mild lows in the upper 60s to
around 70.
&&
.Aviation...(00Z TAF Issuance)
Issued at 730 PM EDT Mon Jun 11 2018
Multiple rounds of showers and storms will continue through the TAF
period as we remain in an unsettled pattern. Forecast TAFs are
mainly VFR because t-storm coverage is expected to be isld-sct over
the region much of the time. However, it should be noted that MVFR
or lower conditions are possible in any t-storm and may be added to
the TAF sites as confidence increases in storms affecting a site.
This evening, BWG stands the best chance at getting a t-storm in a
moderately unstable airmass south of a warm front. The front is
close enough to HNB/SDF that they may also see a stray storm. LEX
has the least chance for a t-storm, but many boundaries in the area
exist from earlier storms and could cause convection near LEX.
Overnight generally expect a decrease in storm strength and coverage
with showers more common during the pre-dawn hrs. More t-storm
chances are expected for Tues afternoon/evening.
Winds will generally be SW-W for much of the TAF period at most
sites. The exception for that is this evening at SDF/HNB/LEX with
winds from the E for a time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Update...RJS/AMS
Short Term...KDW
Long Term...BJS
Aviation...AMS
Area Forecast Discussion
National Weather Service Lubbock TX
644 PM CDT Mon Jun 11 2018
.AVIATION...
VFR conditions will prevail for the next 24 hours. There is slim
chance of TSRA in the vicinity of the terminals toward the end of
the forecast period.
&&
.PREV DISCUSSION... /issued 308 PM CDT Mon Jun 11 2018/
DISCUSSION...
RAP analysis shows a high pressure ridge building in stronger over
West Texas this afternoon, with not a cloud in the sky as of 2 PM.
Hurricane Bud was just making his way onto the CONUS view of
satellite in the Eastern Pacific, roughly 450 miles south/southeast
of the southern tip of the Baja. Bud will make an appearance in this
manuscript later. Otherwise, the high shows no signs of moving
residency until at least the end of the weekend.
Kept highs on Tuesday on the low end of guidance across most of the
CWA as we seem to be struggling to reach anticipated highs today.
Part of that is slightly due to a weak cold front that pushed
through earlier today, but we have also gotten some much needed
rainfall over the past several days. Moisturized ground around here
can pull a real doozy on afternoon highs. The effect won`t be as
pronounced by tomorrow, but it should be just enough to justify the
low end of guidance. As for convection tomorrow, the best shot will
indeed be in the Texas Panhandle, though, it can`t be ruled out that
storms make it into the northern tier of counties in the evening.
Especially if the convection is dying as it heads south, wind will
be a fairly good threat.
Lowering thickness on Wednesday will give some relief, bringing
temps down at least a few degrees. The ridge shifts east by the
weekend with upper troughing digging from the Pac-NW. Now we bring
in Bud. Hurricane Bud should be but a depression by Saturday, but he
could still do some good. Depending on how far east that ridge
moves, Bud`s moisture could move into our area. Models are not yet
in agreement on this solution. In fact, at this point, Bud`s big
benefactor appears to be our neighbor, New Mexico, but there are
model solutions pulling the Pac-NW trough south, the ridge east,
and creating a great corridor for moisture...enough for both NM
and West Texas to share. Here in West Texas, we could also benefit
from a decaying tropical system in the Gulf, but that is much too
far out to be seen. At this point, let`s say our chances for
decent, multi-day rain late this weekend into early next week are
the best they have been in a long, long time. Bud, you`re welcome
in Texas anytime!
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
33
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1010 PM EDT Mon Jun 11 2018
.SYNOPSIS...
A cold front will stall south of the region overnight with high
pressure building in from the north. The front will slowly lift
back north on Tuesday as it weakens. High pressure offshore
will dominate Wednesday and Thursday. Another cold front will
move through by the end of the week followed by high pressure
building in from the north over the weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 1000 PM Monday...Only change with update was to drop tstm
mention over southern sections after midnight. Precip coverage
continues to diminish with front south of area but latest meso
models continue to indicate some scattered light shower threat
overnight, thus keeping lingering low chance POPs.
/Previous discussion/
As of 230 PM Mon...Numerous showers and thunderstorms cont to
grad push S over the srn tier this aftn along and just ahead of
the cold front. This convection plus residual rain will result
in high pops srn tier into the evening. Large cape values wl
cont threat for a few damaging wind gusts next few hrs srn
sections along with frequent lightning and very heavy rain. More
stable air is pushing in across the N behind the front and most
mdls not showing much precip so lowered pops significantly with
mainly shra. Later tonight as front pushes S expect decreasing
precip chcs srn sections. Lows will be mainly in the 65 to 70
dgr range.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
As of 230 PM Mon...Front will slowly begin to lift back N
Tuesday. Moisture will remain quite high and with some weak
short wave energy crossing expect good cvrg of shra and a few
storms, especially in the aftn. Increased pops a bit to likely
over the SW 2/3 rds of area with chc far NE. Clouds and mainly
onshore flow will result in cooler highs mainly 80 to 85.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
As of 4 AM Monday...Unsettled weather expected much of the work
week with a moist unstable airmass in place and a frontal
boundary in the vicinity. A stronger front is expected to push
across the area late in the week with drier conditions next
weekend.
Tuesday Night...A front is expected to be gradually lift back
north Tuesday evening. Frontal convergence, weak shortwave
energy moving through flow aloft along with a moist and unstable
airmass in place, expect scattered showers and thunderstorms
across the area during the evening hours.
Wednesday through Friday...The front lifts back north of the
area by Wednesday with shortwave energy and an attendant
surface low tracking from the Great Lakes into northern New
England. Models continue differ whether the trailing cold front
briefly pushes into the area late Wednesday night/early
Thursday before lifting back to the north. The GFS/CMC are a bit
stronger with the front pushing into the area with enhances
showers/thunderstorms Wednesday night but this isn`t supported
in the ECMWF. A stronger upper level system dives south across
the eastern CONUS late in the week with a stronger cold front
progged to push across the area. Models are not in very good
agreement with the strength of the upper level system or the
timing of the front. The ECMWF is stronger and faster with this
system pushing into the area Thursday night into Friday while
other global models are slower and a bit weaker holding off
until late Friday or early Saturday. Predominantly SW flow will
bring very warm conditions with highs in the upper 80s/lower
90s inland and mid/upper 80s coast.
Saturday and Sunday...The northern stream system continues to
push south across the area Saturday but there is quite a bit of
model spread with the evolution of the upper level system and
potential surface low development off the coast. Models are even
trying to develop a cut-off low somewhere off the Southeast
coast late in the weekend. While large model differences are
leading to a low confidence forecast as we move into next
weekend, it does appear we may briefly move into a period of
drier conditions and a more comfortable airmass, especially on
Sunday.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Short Term /through 00Z Wednesday/...
As of 730 PM Monday...Cold front has pushed south of area and
will stall overnight. Current mix of VFR/sub- VFR will persist
next few hours as lingering showers diminish, then widespread
IFR CIGs expected all sites late evening into Tue morning
underneath developing frontal inversion. As front begins to lift
north Tuesday, CIGs expected to lift to VFR by afternoon but
scattered tstms will develop as well.
Long Term /Tuesday through Friday/...
As of 430 AM Monday...Unsettled conditions expected to prevail
through the period with a moist unstable airmass in place and a
frontal boundary across or near the area much of the period.
Pred VFR expected outside of convection except during the late
night/early morning periods when patchy fog will be possible
each day.
&&
.MARINE...
Short Term /Through Tue...
As of 1000 PM Monday...No changes with this update as gusty NE
surge continuing over northern and central waters.
/Previous discussion/
As of 830 PM Monday...NE wind surge has increased over northern
and central waters and posted/adjusted SCA there including
sounds and Alligator River. Leaned toward latest HRRR which has
good handle on current obs. Ocracoke Inlet to Cape Lookout will
see a few hours of gusts to 25-30 KT as well but do not expect
long enough duration to post SCA there at this time. SCA for
sounds/river will run until late tonight while elevated seas
will keep SCA outer waters through Tuesday.
/Previous discussion/
As of 230 PM Mon...Cold front will cont to push S thru srn tier
this evening before stalling. Gusty NE winds will grad develop
espcly nrn and central wtrs tonight and cont into Tue with winds
becoming more ESE Tue. These winds will result in seas grad
building to 5 to 7 feet central and nrn wtrs and cont SCA N of
Ocracoke. Wind gusts will approach SCA lvls on sounds but for
now will keep just below and cont to monitor. Winds will be a
bit lighter srn wtrs with speeds mainly 15 kts or less and seas
2 to 4 feet.
Long Term /Tuesday night through Friday/...
As of 430 AM Monday...SCA conditions expected to continue
through Tuesday evening across the northern and central coastal
waters. Another chance for SCA conditions will be possible
across the central and southern coastal waters late Wednesday
into Wednesday night.
A front is expected to lift back to the N Tuesday evening. The
front may dip back into the area Wednesday night/early Thursday
but not all models showing this happening leading to lower
confidence in winds this period. S to SE winds around 5-15 kt
Tuesday night becomes SW by early Wednesday, which increases to
10-20 kt during the afternoon and could be as strong as 20-25 kt
late Wednesday afternoon and evening across the southern and
central waters as gradients tightening in response to a low
pressure area passing to the north and the attendant cold front
approaching the area. The trailing cold front briefly push into
the northern waters but guidance is not in best agreement
whether this will happen. Another front may push into the area
sometime Friday or Friday night but models are not in good
agreement with this system either.
Seas expected around 5-7 ft northern/central waters and 2-4 ft
southern waters Tuesday evening, which is expected to subside
to 2-5 ft late Tuesday night/early Wednesday, highest north.
Seas briefly build to 4-6 ft across the southern and central
waters late Wednesday and Wednesday night in response to
stronger SW flow. Seas currently progged to be around 2-4 ft on
Thursday and 2-3 ft Friday.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...Small Craft Advisory until 5 AM EDT Tuesday for AMZ130-131-135.
Small Craft Advisory until midnight EDT Tuesday night for
AMZ150-152-154.
&&
$$
SYNOPSIS...RF
NEAR TERM...RF/JBM
SHORT TERM...RF
LONG TERM...SK
AVIATION...JBM/SK
MARINE...RF/JBM/SK
Area Forecast Discussion
National Weather Service Pocatello ID
148 PM MDT Mon Jun 11 2018
.SHORT TERM...Tonight through Thursday. A low pressure trough
sweeping east through Canada was producing an enhanced westerly flow
aloft across SE Idaho this afternoon with advisory level winds
across the INL and lake wind speeds across the American Falls
Reservoir. The trough works east of the area overnight supporting a
dry northwest flow aloft and decoupling winds around sunset. As
winds decrease, we should see overnight lows drop toward freezing in
the Snake River Plain and Eastern Magic Valley and thus we will
continue the Frost advisories in those valley zones Tuesday morning.
For Tuesday and Wednesday, a modest short-wave ridge and warmer
temperatures transition east through the region ahead of another
approaching Pacific trough. The models suggest that the trough will
shift east through Canada Thursday very much like the current
disturbance resulting in breezy and cooler conditions (5-10 degrees
of cooling). We might also see a slight chance of showers up along
the Montana border. Huston
.LONG TERM...Thursday night through next Monday night. Long wave
pattern is non-existent/featureless for southern Idaho southward to
the border, except for one period: On Fri/Fri Night, an upper level
trough moves into the Great Basin. The rest of the time, the main
energy is very far to the north, in the Northwest Territories and
Nunavut. This leaves the forecast area at risk of diurnally-driven
thunderstorm and shower activity, as any kind of humid unstable air
can move this far north. However would expect PoPs to be low. For
the upper level low evidenced in the long wave pattern on Fri/Fri
Night The GFS this morning had borderline likely PoPs for Pocatello--
but on Sun, and solid likely PoPs for Rexburg and Idaho Falls (for
Sat and Sun). Diminishing precipitation threat for Mon. Thus will
increase substantially the PoP for Sat and Sun afternoons/eves.
Messick
&&
.AVIATION...Whatever clouds are left over from the low that moved
through on Sunday should be gone by this evening, with most of
airdromes showing unlimited CIG by this afternoon. The main forecast
problem today is wind. Fortunately for the valley airports it should
be aligned with the major runway. Biggest problems will be with KSUN
and the uncertainty of westerly wind getting down into the Wood
River Valley, and similar dilemma with KDIJ in the Teton Valley.
KDIJ appears as though it could be very windy there (25G35KT) in a
downslope situation off of the west side mountains. Expecting gap
wind at KSUN, but would not be surprised if the wind just goes light
and variable at the surface, with some strong low-level wind shear.
Since the NAM and HRRR guidance wants to bring the strong west-
southwesterly wind to the surface, have done that--for now. Pushed
back the onset of gusty wind for the valley airdromes. KSUN and KDIJ
expected to start being gusty by 11/18Z. The wind should not make
such a strong return on Tue, and skies should be SKC with unlimited
VSBY. Messick
&&
.FIRE WEATHER...The second of two disturbances will
cross northern Idaho today. Isolated rain showers will occur this
morning mainly north of Challis and Monida Pass. By early afternoon,
most of the moisture and any showers will be moving quickly into
Montana. Windy conditions are expected again today in the Upper
Snake Plain, and rather "breezy" conditions in the Lower Snake
Plain. A Wind Advisory is in effect for the Arco Desert area 1000 to
1900 hours. Tuesday will be sunny and dry, with temperatures
continuing to rebound off the cold temperatures of Sunday. Most
valley areas will be solidly in the 70s, and a few 80F values
observed in the Raft River area. Afternoon humidity around Craters
of the Moon and Challis are expected to dip into the lower and
middle teens. Models still favor tracking our next disturbance
across Washington and the north half of Idaho late Wednesday night
and Thursday. A cold front should cross the Salmon-Challis NF
Wednesday night with a chance of showers, while the Snake Plain
should see a slight chance of showers and thunderstorms Thursday,
along with another windy day from Shoshone to Dubois. Friday and
Saturday will be 10 to 15 degrees cooler with scattered showers
under a much broader low pressure disturbance. RS
&&
.HYDROLOGY...Due to the cooler weather, most river levels were
steady or falling. Little change is expected over the next day or so
as temperatures gradually warm through mid-week. Advisories continue
for Antelope Creek and the Big Wood at Hailey. The warning for the
Snake River near Menan has been replaced by an advisory as releases
from Palisades have been curtailed. Huston
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 2 AM tonight to 9 AM MDT Tuesday for
IDZ017-020-021.
Lake Wind Advisory continues through 8 PM MDT this evening for
IDZ021.
Wind Advisory continues through 8 PM MDT this evening for IDZ020.
&&
$$
Area Forecast Discussion
National Weather Service Pueblo CO
339 PM MDT Mon Jun 11 2018
.SHORT TERM...(This evening through Tuesday)
Issued at 339 PM MDT Mon Jun 11 2018
...Strong to severe storms possible across the Southeast Plains
tomorrow afternoon...
Current water vapor imagery and upper air analysis indicating weak
westerly flow aloft across the area, with faster zonal flow aloft
across the Northern Tier and upper level high pressure in place
across the Southern Rockies through the Southern High Plains.
Current satellite data also indicating mainly clear skies across the
area, with smoke from the 416 Wildfire in southwest Colorado evident
and starting to spread to the east within the westerly flow aloft.
At the surface, breezy east to southeast winds 15 to 25 mph have
developed across the Plains this afternoon, behind last night`s
passing backdoor cold front, with current temperatures some 10-15F
cooler than this time yesterday across Eastern Colorado, mainly in
the 70s and 80s. Further west, temperatures fairly similar to
yesterday in the 60s to 80s at this time.
Tonight and tomorrow...No big changes to current forecast as
generally weak westerly flow aloft will continue as across the
region, with a slight increase in the flow aloft expected through
the day tomorrow, as a minor embedded wave looks to translate east
across the Northern Tier.
For tonight, with the smoke plume evident in satellite imagery and
HRRR smoke plume forecast, have kept the mention of smoke across the
Southwest Mts through the southern portions of the San Luis Valley
into early tomorrow morning. Will keep smoke out of the forecast
further east, as plume should continue to thin out and disperse,
however, can`t rule out some hazy conditions across southern
portions of the Eastern Plains into tomorrow morning. Should see
winds diminishing through the evening, leading to overnight lows
around seasonal levels in the 40s and 50s areawide.
On Tuesday, low level moisture increases within the persistent low
level easterly upslope flow across Eastern Colorado, which will lead
to better chances of convection through the late afternoon across
the Plains. Models hinting at the Palmer DVD and Raton Mesa for
convective initiation tomorrow afternoon, which is juxtaposed with
the upslope flow. If storms can form and push east into better low
level moisture and instability (capes of 1500-2500 j/kg), there will
be enough shear with the westerly flow aloft to support more
organized convection and the potential for severe storms, producing
large hail and damaging wind gusts across the Southeast Plains.
Current SPC Day2 outlook has a marginal risk of severe storms across
the I-25 Corridor with a slight risk east of the Corridor to the
Kansas border, which still looks good.
Further west, dry conditions to persist, though can`t totally rule
out isolated diurnal high based convection across the higher
terrain. Temperatures tomorrow look to be at to slightly warmer than
today, mainly in the 80s to lower 90s across the lower elevations,
and mainly in the 60s and 70s and the higher terrain.
.LONG TERM...(Tuesday night through Monday)
Issued at 339 PM MDT Mon Jun 11 2018
Primary longer term meteorological concerns include temperatures,
elevated near critical to critical fire weather conditions at
times and pops.
Recent longer term PV/Precipitable water analysis, computer
simulations and forecast model soundings parameters suggest that
thunderstorms, some strong to potentially severe(favoring eastern
locations) will be possible from Tuesday evening into Tuesday
night and have inserted severe wording into grids/zones over
favored locations during this time-frame.
Zonal to southwesterly upper flow over the forecast district is
expected to produce above seasonal temperatures in combination
with isolated to low-grade scattered showers and thunderstorms
Wednesday and Thursday with scattered pops then anticipated over
western portions of the CWA Friday. In addition, localized/elevated
fire weather concerns will be possible at times from Wednesday
into Friday.
Then, the potential exists that a more active/moist pattern may
develop over the forecast district from this weekend into next
week as south-southwesterly flow draws up remnant moisture from
Hurricane Bud(which is currently approximately 450 miles to the
south-southeast of Cabo San Lucas). Also, additional deep
atmospheric moisture from the Gulf of Mexico has the potential
of impacting the forecast district with increased pops(including
the potential for locally heavy rainfall at times next week). As
always, WFO Pueblo will closely monitor latest systems/trends and
adjust forecasts as needed.
Finally, above seasonal mid-June maximum and minimum temperatures
are anticipated over the majority of the forecast district into
this weekend, with maximum temperatures expected to decrease by
several degrees from later this weekend into next week as deeper
atmospheric moisture arrives.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 339 PM MDT Mon Jun 11 2018
VFR conditions are expected at COS and PUB over the next 24 hours.
Breezy east to southeast winds 15-20kts are expected at COS and PUB
through the afternoon, as low level upslope flow continues behind
this mornings dry cold front. A more diurnal wind regime is expect
tonight and tomorrow, with possible late after convection across the
higher terrain. Can`t rule out a late afternoon thunderstorm at COS,
though will not carry in the TAF at this time. Storms that develop
and can push east across the Southeast Plains could become severe
late tomorrow afternoon and evening.
VFR conditions with a diurnal wind regime can also expected at ALS
through the period. However, some lowered visibility in haze and
smoke from SW CO wildfires can not be ruled out.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Charleston WV
1012 PM EDT Mon Jun 11 2018
.SYNOPSIS...
Unsettled conditions expected through mid week. Front late
Wednesday may reduce rain chances for the end of the week.
&&
.NEAR TERM /UNTIL 2 AM TUESDAY MORNING/...
As of 1010 PM Monday...
Will tweak the pops and sky cover a bit overnight to better
represent current trends.
As of 605 PM Monday...
Will update pops to adjust for current radar and HRRR trends for
late this afternoon and early this evening.
As of 105 PM Monday...
Latest surface map shows a stationary front was located across
portions of southeast Ohio and the northern counties of West
Virginia. This boundary and a mid-level disturbance was
resulting in widespread showers across much of the region.
Have not seen much in the way of thunderstorms. However, still
can not rule one or two out until around sunset.
Some areas across our northern counties have seen rainfall
amounts around or in excess of an inch. The showers should be
exiting the areas where the heavier rain fell and do not expect
to see any water issues.
Areas farther south could still see some heavier rain amounts
this afternoon as PWAT values are still quite high. Will have to
continue to watch rainfall amounts. However, do not expect any
water issues at this time.
The boundary is forecast to push south tonight with drier air
filtering in from the northeast. Northern portions of the area
should be dry with some showers possible across the south.
The front will begin to return back north as a warm front on
Tuesday with precipitation chances increasing from the
southwest.
Models suggest thunderstorms will be possible and have continued
mention of storms in the forecast.
Clouds and precipitation have acted to keep temperatures cooler
than expected today. MAV guidance is warmer for highs on Tuesday
than MET guidance. Believe there will be enough breaks in the
clouds for temperature to warm to near MAV numbers. In addition,
a blend of temperature guidance shows values close to the MAV
and will generally be followed.
Also used a blend of guidance for lows tonight.
&&
.SHORT TERM /2 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
As of 345 PM Monday...
Shower and thunderstorms chances remain high through Wednesday
evening as a frontal boundary works slowly across the region.
PWATS remain elevated so some localized flooding will be a
possibility due to the repeating rounds of showers and storms
that are expected. Temperatures are tricky due to cloud cover
and rain potential so stuck with the blended model guidance
which offers lows in the 60s and highs in the muggy 80s for most
locations.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 345 PM Monday...
Cold front sinks south of our region on Thursday...but just
barely. Behind this front, models indicate that a drier airmass
will advect into much of the area with dewpoints falling into
the 50s and low 60s by late Thursday into Thursday night. This
should quell our shower/storm chances for a time, but the
airmass slowly modifies as we go into the weekend bringing a
renewed threat for precip. The blended model guidance PoPs were
fairly high considering the strength of the ridge building
overhead and low initial dewpoints. So, pared PoPs back some and
made them more diurnal in nature and focused on the higher
terrain Friday and Saturday afternoon before smearing them out
over the entire CWA Sunday into Monday. A complicating factor is
MCS potential with the area remaining in northwest flow through
the weekend and on Monday as the ridge builds in but
predictability is too low to factor that in right now.
There will be no big change in temps behind the front, except
for lows Thursday night which should take advantage of the lower
dewpoints to fall into the comfortable 50s to low 60s. The
mercury will then inch upwards through Monday as the ridge
builds in.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
As of 605 PM Monday...
A frontal boundary will linger across the area overnight, then
push back northward on Tuesday. This will allow for some
restrictions in showers and thunderstorms at times.
Tonight is a tough forecast regarding fog. Some areas got an
abundance of rain, but there will be some flow overnight.
Confidence in whether fog will form or not is low.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z WEDNESDAY...
FORECAST CONFIDENCE: Low.
ALTERNATE SCENARIOS: Timing and restrictions in showers and
thunderstorm could vary. Fog may or may not form overnight.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE TUE 06/12/18
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H M M M H H H
HTS CONSISTENCY H H H M M M M M M L M L
BKW CONSISTENCY H H H M H H M M M M L M
EKN CONSISTENCY H H H H H M M L L L L M
PKB CONSISTENCY H H M H M L M M M M H M
CKB CONSISTENCY M M M M M H H H H H H H
AFTER 00Z WEDNESDAY...
IFR possible in scattered storms Tuesday night and Wednesday.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.
&&
$$
SYNOPSIS...ABE/JSH
NEAR TERM...JSH/RPY
SHORT TERM...ABE
LONG TERM...ABE
AVIATION...RPY
Area Forecast Discussion
National Weather Service Topeka KS
819 PM CDT Mon Jun 11 2018
.MESOSCALE DISCUSSION...
Issued at 752 PM CDT Mon Jun 11 2018
Convection has begun to backbuild to the southwest along the cold
front near the KS/NE state line. MLCAPE on the order of 4000 J/kg per
the TOP 00z sounding still supports the potential for large hail
over the next few hours. Rapidly developing updrafts within the
extreme instability has caused enhanced stretching of the pre-
existing vorticity along the cold front/cold pool, which has
resulted in a few tornadoes in southeast NE. Recent short-term
model guidance is trending towards an increase in the effective
SRH with values reaching 200-300 m2/s2 as the low-level jet
strengthens. This environmental SRH along with the baroclinic
generated vorticity associated with the leading of the gust front
fosters the threat for tornadoes to continue through the late
evening. The latest analysis also shows DCAPE of 1500 J/kg ahead
of the mesoscale convective complex that could favor damaging wind
gusts through the early morning. Also, the warm moist air mass in
place may prohibit rapid cooling of the boundary layer, which
could limit the strength of the nocturnal inversion increasing the
likelihood of severe wind gusts to reach the surface.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 311 PM CDT Mon Jun 11 2018
A surface boundary was noted across central Kansas this afternoon
with temperatures soaring into the upper 90s ahead of this feature.
With dewpoints in the lower 70s and steep mid-level lapse rates,
vast instability has overspread northeast Kansas with CAPE over 4000
J/kg. The front is expected to progress eastward this evening with
thunderstorms initiating in Nebraska, building down into the CWA.
With initial storms forming along the boundary, helicity values
indicate a tornado will be possible although the better chances look
to be north of the area in Nebraska. The main hazards with storms
this evening may be strong winds and hail as storms begin to cluster
and become cold pool driven. Storm motion will be on the slower
side and with PWAT values above average (2 to 2.5 inches) ahead of
the boundary, heavy rainfall may be another concern as storms form
parallel to the boundary. Even with the potential for some training
storms, flooding should remain isolated as the front steady
progresses southeast. CAMs have been in decent agreement with
initial storms forming near the Kansas/Nebraska boarder and moving
southeast across the entire area. The bulk of precipitation is
expected to be south of the area after roughly 2AM this morning,
with the HRRR indicating the potential for some lingering showers
and storms in east central Kansas through the early morning.
Not too much relief in the form of temperatures Tuesday after this
frontal passage with highs tomorrow in the upper 80s and low 90s.
Dewpoints may be slightly cooler and heat indicies will stay below
100 degrees. Dry conditions are forecast through the afternoon as
high pressure noses in from the north (centered over South
Dakota).
.LONG TERM...(Tuesday night through Monday)
Issued at 311 PM CDT Mon Jun 11 2018
For Tuesday night into Wednesday morning, elevated thunderstorms
are possible. Models show upslope flow into the central high
plains which could favor convective development west of the area.
Then by Tuesday evening, models expect an 850MB front to be east
to west across the forecast area with the low level jet providing
convergence along the boundary. The better moisture and
instability is expected to be mainly across southern KS, but
storms could impact areas along and south of Interstate 70 where
the 850MB boundary is progged to be. Another round of elevated
storms is possible Wednesday night as models develop return flow
with the low level jet nosing into northeast KS.
By Thursday afternoon, mid level heights are expected to rise as
models develop ridging over the central plains. This ridging is
expected to persist through the weekend with little to no dynamic
forcing affecting the forecast area. So hot and dry weather is
forecast for Thursday through Sunday with lows in the 70s and
highs in the mid to upper 90s. There is heat concerns for this
time period as there could be a string of days with heat indices
approaching 105 degrees.
There are signs of a frontal system moving into the plains Sunday
night or Monday. Because of this there are some low end POPs
Sunday night and Monday. However confidence in this frontal timing
is low as the ECMWF wants to maintain the upper ridge over eastern
KS.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 639 PM CDT Mon Jun 11 2018
Will maintain a watch for convective trends this evening as cells
develop along a frontal boundary. Additional storms may move south
out of Nebraska. Current thinking is for TSRA near MHK by 02Z and
at TOP and FOE around 03Z. Short term models suggest that the
storms may move south of the terminals by 06Z. Winds will shift to
the northwest behind the frontal boundary.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE...Sanders
SHORT TERM...Heller
LONG TERM...Wolters
AVIATION...53