Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/20/19
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1027 PM EDT Wed Jun 19 2019
.SYNOPSIS...
Scattered showers and thunderstorms this afternoon should diminish
this evening. Humid conditions continue tomorrow as a low pressure
system arrives bringing areas of widespread rain along with
scattered thunderstorms. Heavy rain along with some strong to severe
storms are possible. High pressure then builds into the Northeast
this weekend leading to pleasant, dry and sunny conditions.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 1020 PM EDT...Decreased PoPs/Wx impacts for the next
several hours before additional convection evolves overnight. As
seen in the 00Z sounding, while not too steep lapse rates, PWATs
continue to climb (now up to 1.55") steadily as the wind field
remains rather light in the lower levels of the troposphere.
However, per the H2O vapor loop, rather zonal flow across the
northeast corridor continues with a diffuse frontal zone(s)
nearby. However, latest 18Z/00Z runs and HRRR suggest the low
level convergence will increase overnight to the north of Albany
as low level jet magnitudes increase and converge across these
northern areas. Meanwhile, southeast marine layer too will
advect northward where some additional showers could develop.
Overnight lows look in good shape with minimal enhancements
needed at this time.
Prev Disc...
Scattered thunderstorms and showers continue in the
Mohawk and Schoharie Valley into the southern Adirondacks as
well as the Green Mountains and northern Berkshires associated
with weak warm air advection and differential heating/mixing
boundaries. Given dew points in the mid-60s and PWATs ranging
1-1.5 inches, some of these storms have produced heavy downpours
but due weak forcing, none have become severe. We have issued a
few Special Weather Statements to account for poor drainage
flooding and gusty winds below severe criteria. Showers and
storms diminish this evening but we will remain muggy and mild
under cloudy skies.
A low pressure system developing in the Great Lakes will head
eastward tonight with height falls ahead of the approaching
shortwave encroaching into our southwestern zones after 09z/10z.
Therefore, we trended POPs back to chance towards sunrise to
account for a few scattered showers. Widespread rain still
looks to hold off until after 12z/20 as per latest hi- res
guidance.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
Heavy rain and some urban/poor drainage flooding continues to
be a concern for Thursday as an anomalous low pressure from the
Great Lakes intensifies as it moves into the Northeast. In the
morning hours, we will be monitoring a potential band of
widespread rain associated with the developing system`s
deformation zone that looks to gradually shift into the
Adirondacks. There are still some differences latitudinally on
the exact track of the low and thus, the placement of the
tightest baroclinic zone among the global guidance. However, the
general consensus shows that low tracking through the Greater
Capital Region which would keep the deformation zone and best
convergence in the Adirondacks, Mohawk Valley into the Lake
George/Saratoga Region meaning this areas have the greater
potential to experience a widespread period of rain, mainly
towards mid to late morning into the afternoon.
The system`s warm sector may reach into the mid-Hudson Valley
and the Catskills during the afternoon and should this area see
some breaks of sun midday/early PM, dew points will be plenty
moist near 70F to generate some instability. Given the track of
the low, the amount of sun is uncertain but with 30-40kts of
deep layer shear, some strong to severe storms in this region
cannot be ruled out. SPC is also in line with this thinking as
it adjusted its marginal risk northward this area. Any
thunderstorms will be capable of heavy downpours and some poor
drainage flooding.
A shortwave trough digging southward from Canada looks to
partially phase with the shortwaves associated with this
developing low Thursday evening which should allow our surface
low to intensify. In fact, there is good consensus with this
low deepening below 995mb which for mid-June is quite
impressive. As a result, the aforementioned deformation zone
looks to shift southeastward through eastern NY and western New
England Thursday night into Friday morning. With PWATS near 2
inches, periods of heavy rain are a concern with some areas
potentially seeing repeated heavy rain as the deformation may
pivot over some areas. Areas from the Greater Capital Region
northward have the greatest potential for repeated periods of
heavy rain Thursday night and this thinking is in line with
WPC`s Excessive Rainfall Outlook which highlights this area in a
Slight Risk. Held off on a flash flood watch for now but will
have the overnight shift re-evaluate.
Heading in Friday morning, the deformation zone and associated
surface cold front will continue pushing eastward bring the
band of widespread rain through the Capital Region before
exiting western New England by midday. Breezy conditions are
expected in the wake of the front Friday with gusts up to 20-30
mph possible by the afternoon as high pressure quickly from the
Great Lakes quickly takes control. Plenty of mid-level dry air
arrives as well which should help lead to decreasing cloud
coverage. Northerly flow should lower dew points as well through
the day, decreasing the humidity.
High pressure remains in the place for the weekend leading to a
very nice weekend with seasonable temperatures in the 70s, low
humidity and mostly sunny skies.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
The first weekend of summer will end on a good note as latest global
models continue to support the passage of the upper trough with
building heights aloft. While upstream activity is expected to
increase in coverage, we will keep conditions dry with some increase
in cloud coverage later in the day. With June sun angle, and H850
temperatures into the mid-teens, high temperatures should average
near 80F for valley locations and mainly 70s elsewhere.
Sunday night, the aforementioned upstream ridge axis is expected to
slide overhead as upstream warm advection and associated
convection/synoptic-overrunning approaches. So clouds should
increase a bit more but we will continue with a mainly dry forecast.
Overnight lows mainly into the 50s to near 60F for valley locations.
Monday into Tuesday, models divergence continues with the ECMWF the
most amplified with trough and associated surface low across the
Great Lakes with a more progressive pattern offered by the GFS/ICON
models. Either way, a period of more active weather with warm and
humid conditions as highs into the 70s and lower 80s and overnight
lows into the 60s.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
Challenging forecast as conditions at TAF locations are VFR.
This should be rather brief as lower MVFR/IFR flight conditions
are across PA/NJ/CT should advect northward overnight. As for
convection, a VCSH was used at this time through the evening
hours with increase probabilities overnight into Thursday.
IFR conditions expected all TAF sites very late tonight and
likely extend into the daylight hours Thursday.
Winds become light and variable tonight and then increase to
southeasterly at 5 to 15 kt on Thursday.
Outlook...
Thursday Night: High Operational Impact. Definite SHRA.
Friday: Moderate Operational Impact. Breezy Chance of SHRA.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: No Operational Impact. NO SIG WX.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: Moderate Operational Impact. Chance of SHRA...TSRA.
&&
.FIRE WEATHER...
Scattered showers and thunderstorms this afternoon should diminish
this evening. Humid conditions continue tomorrow as a low pressure
system arrives bringing areas of widespread rain along with
scattered thunderstorms. Heavy rain along with some strong to severe
storms are possible. High pressure then builds into the Northeast
this weekend leading to pleasant, dry and sunny conditions.
Thanks to humid conditions, RH values will remain above 50%
through Friday with high temperatures in the 70s. By Saturday,
high pressure and sunny skies along with lower dew points will
lead to RH values dropping to 40-50% during the afternoon hours.
Winds will be light today and tomorrow generally out of the
south or southwest. Gusty northerly winds are expected Friday
up to 20-30mph with breezy winds on Saturday.
&&
.HYDROLOGY...
Total rainfall from our system Thursday into Friday morning
looks to range 0.75 to 2.00 inches. Most of this rainfall is
expected to occur from an organized and impressive low pressure
system that will take place throughout this period. However,
high PWATs near 1.50 to 2 inches is expected along with embedded
convection which means bands of heavy rain and downpours from
thunderstorms may lead to locally higher amounts. As a result,
poor drainage and urban flooding and especially if heavy rain
repeatedly falls over the same area. A Flash Flood Watch was
not issued with this update but we will re- evaluate overnight
as training convection in such a moist environment may lead to
some flash flooding.
Smaller creeks and rivers may reach bankfull due to heavy rain
and thunderstorms but we do not expected rivers to reach flood
stage at this time.
Please visit our Advanced Hydrologic Prediction Service /AHPS/
web page for specific area rivers and lakes observations and
forecasts.|
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Speciale
NEAR TERM...BGM/Speciale
SHORT TERM...Speciale
LONG TERM...BGM
AVIATION...SND/BGM
FIRE WEATHER...Speciale
HYDROLOGY...Cebulko/Speciale
Area Forecast Discussion
National Weather Service Bismarck ND
1009 PM CDT Wed Jun 19 2019
.UPDATE...
Issued at 1004 PM CDT Wed Jun 19 2019
Line of storms over eastern Montana is about to cross into North
Dakota. The northern end of this line has weakened, but southern
end remains strong. Higher instability remains over far southwest
North Dakota, though this tapers off quickly as you go east.
Therefore, will have to watch the severe threat as storms enter
North Dakota, but expect the threat to be short lived.
UPDATE Issued at 646 PM CDT Wed Jun 19 2019
Thunderstorms continue to gradually work east through eastern
Montana, but have been very slow. Therefore it may be another hour
or two until they cross the state line. Otherwise, showers
continue to lift to the northeast over south central North Dakota.
Forecast remains in good shape.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 338 PM CDT Wed Jun 19 2019
Another round of showers and a few thunderstorms is likely tonight
into Thursday morning before coverage of precipitation decreases a
bit by Thursday afternoon.
As of mid afternoon, a leading vorticity maximum continues moving
eastward through south central ND, with forcing for ascent driving
rain to its immediate east. Shallow convection is occurring near
the cold pool of the vorticity maximum, but is being restricted in
its magnitude by cool and relatively stable boundary layer thermal
profiles with minimal MLCIN. Radar trends and CAMs through recent
HRRR cycles -- which have begun to better-capture the leading area
of rain in south central ND into the James River valley -- suggest
the precipitation associated with the lead and weakening vorticity
maximum will continue to move east and diminish by evening.
Meanwhile, insolation is occurring over eastern MT and far western
ND and surface dewpoints in the lower to middle 50s F are expected
to yield 500-1000 J/kg of MLCAPE in a narrow axis of western ND
by late afternoon and evening. Shortwave ridging is occurring over
that part of the state downstream of a stronger upstream impulse
approaching from MT, but convection recently initiating in eastern
MT may move into the state in the late afternoon. We also believe
additional convection will move into western ND by late evening as
stronger forcing for ascent approaches. Given a narrow axis with
weak to moderate instability amid effective shear magnitudes of
25-35 kt there remains a marginal severe storm risk. Otherwise,
showers and a few thunderstorms will likely progress from west to
east tonight and Thursday morning in tandem with the shortwave
trough. By Thursday afternoon, low- and midlevel drying will
progress through western ND and up to the Highway 83 corridor,
favoring increasing surface heating which could in turn generate
some diurnally-driven convection even behind the primary impulse.
.LONG TERM...(Thursday night through Wednesday)
Issued at 338 PM CDT Wed Jun 19 2019
A seasonably cool and unsettled weather pattern will continue
into this weekend in association with an upper-level trough which
will be centered over the Rockies. A strong shortwave trough will
lift out of the mean trough on Friday, with most global model
guidance suggesting a deepening surface to 500 mb low will move
northward across western ND as a trailing cold front moves east
across central ND. Both forcing near the low and cold front could
generate convection, and while the scenario will be characterized
by relatively modest bouyancy owing to weak lapse rates aloft, we
will need to be mindful of the potential for low-topped supercells
in the vicinity of a triple point near the surface low and eastward
along a warm frontal zone in north central ND Friday afternoon if
sufficient destabilization for surface-based storms occurs near
those features. This scenario will feature enhanced vorticity and
low-level shear in the vicinity of the triple point and warm front,
but it`s worth noting that the 12 UTC NAM lifts the surface low
into Canada much earlier, which would alleviate the risk. Moreover,
these scenarios are driven by low-level bouyancy and that typically
has a low degree of confidence until closer in time.
Thereafter, a chance of showers and storms will continue through
the weekend, but coverage will diminish in time given a lack of
larger-scale impulses as the mean trough begins to weaken. By
early next week, a shift in the upper-level pattern will begin
with global model guidance suggesting that midlevel ridging will
develop over the central United States, leading to a warming trend
in the Northern Plains. That evolving pattern could ultimately
also generate increasing low-level moisture, instability, and a
chance of more organized convection in the region toward the
middle or latter parts of next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 646 PM CDT Wed Jun 19 2019
Showers with some embedded thunderstorms continue to bring many
areas of MVFR with localized IFR conditions. This will continue
through tonight into Thursday.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...JJS
Area Forecast Discussion
National Weather Service Columbia SC
941 PM EDT Wed Jun 19 2019
.SYNOPSIS...
The pattern of mainly diurnal thunderstorms will persist through
Thursday with the potential for severe thunderstorms Thursday
afternoon and evening. There will be a break on Friday with
drier air over the area and a frontal boundary to the south.
That front will lift northward Saturday bringing back
thunderstorms to the forecast, potentially severe. The front
will become diffuse over the weekend under upper ridging through
early next week. This will support a pattern of afternoon
thunderstorms and above normal temperatures in the long term.
&&
.NEAR TERM /UNTIL 7 AM THURSDAY MORNING/...
With the loss of daytime heating convective activity across the
region has dramatically diminished. However, there are still
isolated storms over the Upstate in association with the lee-
side surface trough. Do not expect these to impact the local
forecast area. Skies will remain partly cloudy through the night
and a low level jet will provide some boundary layer mixing, so
expect lows in the low to mid 70s.
&&
.SHORT TERM /7 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
The main concern is a threat of severe thunderstorms Thursday
afternoon and evening.
There will be two features capable of producing thunderstorms on
Thursday. First, a decaying MCV is projected by most CAMs on
Thursday morning over the TN/AL/GA area. The outflow from this
system and associated vorticity maxima will be over the forecast area
late morning or early afternoon. Thunderstorms may redevelop along
this feature. Next, the vorticity maxima associated with the main
shortwave will approach the FA later in the afternoon, better
aligned with peak heating. Surface convergence along a lee-side
trough should trigger additional convection as the shortwave passes.
Although drier west winds and earlier convection may limit
thunderstorm coverage.
The greatest chance for severe weather will be in the afternoon and
into the evening as the main shortwave moves across the FA.
Instability will likely be moderate with models/SREF probabilities
suggesting sbCAPE values between 1500 and 2500 J/kg. Whether this is
realized will depend largely on the extent of convection earlier in
the day. 0-6 km bulk shear will be strong for this time of year,
around 30kts, suggesting organized convective lines may develop. Dry
air aloft, steep mid and low-level lapse rates, and moderate sheer
suggest the main hazard will be areas of damaging winds. The threat
of thunderstorms will diminish overnight in the wake of the
shortwave trough.
Highs during the day will range from the upper 80s to low 90s. It
will be breezy during the afternoon with gusts up to 25 mph but
should remain below Lake Wind Advisory criteria. Lows will be around
70 degrees.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
There will be a brief period of drier weather Friday before another
chance for severe weather on Saturday.
An upper level trough will lift out of the Northeast on Friday. This
will push a trailing frontal boundary south of the forecast area
with drier air behind it. Downslope flow will also contribute to
dry, warm weather. Forecasted temperatures a little higher than the
guidance consensus because of downslope flow.
Saturday, the models have been consistent lifting the frontal
boundary northward into the FA with strong instability south of the
front. Convergence along the front will likely trigger thunderstorms
during the afternoon. The strong instability and dry air aloft will
support the threat of damaging downburst wind and hail.
For much of the remainder of the period, the GFS and ECMWF show
upper level ridging over area. The ridge will be strongest this
Sunday, weakening into early next week. Surface ridging will
also extend from the Atlantic into the Gulf of Mexico. This
pattern supports warm weather with scattered diurnal convection.
There may be a series of shortwave troughs moving along the
northern periphery of the ridge which will support convective
development at times. Guidance suggests above normal
temperatures with highs mainly in the middle and upper 90s.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Restrictions possible in early morning stratus otherwise
generally VFR conditions expected.
Isolated convection remains around the region this evening but
generally waning with sunset and do not anticipate terminals
being impacted. Winds will stay up overnight around 5 to 10
knots with a 30-35 knot low level jet keeping the boundary
layer mixed.
Ample low level moisture supports the possibility of early
morning stratus again on Thursday although confidence is limited
as guidance is mixed and HRRR not showing any as it has the past
two nights. Fog is not expected due to the 30 low level jet.
Showers and thunderstorms expected to develop across the area
on Thursday as a decaying MCS moves into the region and
instability increases. Breezy west-southwest winds will
increase to 10-20 kts with gusts 20 to 25 knots by late
morning.
EXTENDED AVIATION OUTLOOK...Widespread convection possible into
Thursday night as a cold front crosses the area. Isolated
diurnal showers and thunderstorms possible Saturday and Sunday.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service State College PA
1204 AM EDT Thu Jun 20 2019
.SYNOPSIS...
An unsettled and stormy weather pattern will continue through
Thursday evening thanks to the close proximity of a slowly
meandering front. A pleasant and dry weekend is in store.
Temperatures will trend a little cooler than normal for Friday
and Saturday in the wake of a cold front. Warmer weather will
return next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
The convection has been scattered about and locally heavy, but
most rain has been brief enough to cause only minor problems if
any at all.
The very humid airmass will remain in place overnight, and the
HRRR suggests the risk of showers/storms will continue. No real
organized feature is evident so it`s hard to be specific with
timing and location, but the overall trend should be for the
activity to diminish in coverage over the next few hours, and
that seems to be the trend even now.
Convection rolling through central OH is brought into my
western zones right around sunrise. As it stands now the Flood
watch expires at 04Z/midnight. That seems reasonable, but
looking ahead to late night and Thursday morning, we may need a
new watch for additional heavy rain potential.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
A distinct low center will develop and push into wrn PA in the
morning hours. This low is sub-1000mb and anomalously strong for
the beginning of Summer. It will push its southward trailing
cold front through during the afternoon and early evening. The
coincidence of the old west-east front, anomalously high PWATs,
and this decent long- wave trough + sfc low moving thru around
peak heating will generate thunderstorms. Some of them will
produce very heavy rainfall, and severe wind gusts/hail with as
increasing vertical shear and a veering/broad loop hodograph.
An isolated tornado or two is possible as well due to the
boundary/shear and low LCLs present - especially from the
KUNV/KIPT vicinity SE to the Lower Susq Valley.
The heavy rain will probably cause some flooding, but the
flooding threat area is not highly certain at this point. We may
need a flash flood watch for Thursday, but later shifts can
take a closer look. It`s a little far out to post a watch just
yet.
The potent sfc low pressure center (~995 mb) should be over NE
PA by nightfall, and the cold front dragging down thru MDT. Wrap
around could make some sct SHRA over the W Thurs night, but it
will be drying out and getting a little gusty by Fri morning.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
Breezy and drier/less humid conditions will arrive Thursday
night through Friday on the backside of the departing system.
Expect a break from the rain for 2-3 days with pleasant
conditions through the weekend before a surge in humidity
returns showers and storms to the forecast next week.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
Rain continues to move eastward with the strongest storms
moving into eastern PA. The decoupling atmosphere will bring
light winds and IFR and lower cigs and vsbys. UNV has already
gone to LIFR. LNS, MDT, BFD and IPT could go IFR between 05Z to
09Z. So look for areas of fog/low stratus clouds through
Thursday morning. Cigs and vsbys will slowly improve mid to late
morning. Another round of showers and thunderstorms will be
possible late Thursday morning, early Thursday afternoon.
.Outlook...
Thu...Rain/low cigs possible north. Scattered-numerous PM tsra
impacts likely Central and Southern PA.
Fri...AM low cigs possible W Mtns.
Sat-Sun...No sig wx expected.
&&
.CLIMATE...
Astronomical summer (solstice) begins Friday, June 21st at
1154AM EDT (1554 UTC).
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch until midnight EDT tonight for PAZ012-
017>019-024>028-033>036-041-042-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...La Corte
NEAR TERM...La Corte/Lambert
SHORT TERM...Lambert
LONG TERM...Steinbugl
AVIATION...Ceru
CLIMATE...
Area Forecast Discussion
National Weather Service Cheyenne WY
259 PM MDT Wed Jun 19 2019
.SHORT TERM...(This evening through Friday)
Issued at 235 PM MDT Wed Jun 19 2019
Current KCYS radar loop shows isolated thunderstorms in a line
from Douglas southeast to Kimball. A thunderstorm recently moved
through Cheyenne a few hours ago producing brief very heavy rain
and some small hail. Expect impacts to be low with this activity,
at least compared to the last few days, but a few stronger storms
are still possible across east central Wyoming and into the
northern Nebraska panhandle. 0-6km shear is below 25 knots at this
time, but CAPE values around 2000 j/kg may be enough to result in
a marginal severe storms with hail and strong winds the primary
concerns. With the thunderstorms moving to the southeast at a
good clip, flash flooding is not expected. The other forecast
issue through tonight is locally strong winds in and near the wind
prone areas of Arlington/Elk Mountain and Bordeaux. This portion
of the forecast is tricky since we are well out of High Wind
season, but 700-500mb winds are exceptional for this time of the
year with values around 45 knots in addition to a decent surface
pressure gradient along the spine of the Rocky Mountains. Winds
from Rawlins to Laramie have responded a little this afternoon,
but gusts have struggled to increase over 40 mph thus far. Will
keep the High Wind Watch going for now to see how surface winds
respond to decoupling from the environmental winds aloft late this
evening. Confidence is still low-moderate to this event, but can
not rule it out either.
For Thursday, the next Pacific storm system, and associated
strong cold front, will move into Wyoming and rapidly through the
forecast area Thursday evening. Expect a pretty solid coverage of
light-moderate showers and widely scattered thunderstorms to
develop along this cold front late Thursday and Thursday night.
Kept POP between 50-70 percent across most of the area, especially
along the I-80 corridor and across western Nebraska. There is a
marginal risk of strong to severe thunderstorms across most of the
eastern plains east of I-25, but gusty winds look like the main
concern thus far with most of the activity occurring late in the
afternoon through late in the evening. Daytime temperatures will
mostly be in the 70s to low 80s ahead of the cold front.
For Friday, the cooler air will push into the region with high
temperatures back into the 60s, which is around 10 to 15 degrees
below normal. Portions of the western Nebraska panhandle may
briefly achieve highs in the low 70s before fropa. Models show a
cool and showery day under mostly cloudy skies. Can not rule out a
few elevated thunderstorms near the Colorado border.
.LONG TERM...(Saturday through next Wednesday)
Summary: Main focus will be on Saturday and Sunday time frame with
greater shower and thunderstorm likelihood while early to mid next
week looks drier and warmer. Hazards on Saturday and perhaps Sunday
could be pockets of heavy rainfall and a few strong thunderstorms.
Sunday is more conditional at this time depending on pattern
evolution and timing.
Weather Details: Quite active pattern to end the work week going
into the weekend with a large-scale trough over the Northern Plains
back across the Pacific Northwest per multi-model consensus. Several
vorticity maximums and embedded shorter wavelength troughs will
rotate about the parent trough across Wyoming. As a result, a
frontal boundary will shift near and/or bisect southeast Wyoming
late Friday into Saturday as the first shortwave troughs pivots
across north-central Wyoming. With broad synoptic lift and
isentropic upglide over-top the frontal zone, showers will likely
persist Friday night into early Saturday morning. Deeper H7-H5
southwest flow will occur by Saturday, bringing the frontal boundary
north as a warm front while also advecting higher theta-e air into
the region. With greater theta-e air comes greater instability and
coverage of showers and storms should increase Saturday afternoon
with added daytime heating. Not out of the question that some storms
could be strong and also have heavy rain in isolated areas. It
remains to early to pinpoint more favored areas of this possible
heavier rainfall.
Mid-range models diverge on Sunday with GFS much slower on trough
movement while ECMWF more progressive but has slowed vs. the
previous 18/12Z run. Latest operational GFS remains quite bullish on
more rain/storm chances Sunday but will temper these down until
greater mid-range agreement occurs.
For early to mid next week - Warmer and overall drier conditions
look to set up with shortwave ridging occurring over the central
Rockies. While some afternoon high terrain showers/storms could be
possible, coverage compared to the current stretch of wet weather
should be reduced by a good factor.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1132 AM MDT Wed Jun 19 2019
Continued strong winds and isolated showers and thunderstorms
possible later this afternoon into the early evening. Based off
the latest HRRR strongest potential will be on the northern
counties with KCDR seeing more of the thunderstorm activity though
lingering storms may pass near from KCYS eastward. MVFR conditions
at the terminal may be possible with any storms over each site. Models
are also trending to stronger wind field aloft particularly at
KLAR to introduce overnight LLWS there.
&&
.FIRE WEATHER...
Issued at 200 PM MDT Wed Jun 19 2019
Minimal fire weather concerns for the rest of this week and
through the weekend. Although daytime minimum relative humidities
have lowered to around 20 to 25 percent this afternoon across
Carbon county with winds gusting up to 40 mph, recent rainfall
and green fuels will greatly limit any concerns in that area
into Thursday.
&&
.HYDROLOGY...
Issued at 200 PM MDT Wed Jun 19 2019
Flood Warning for the North Platte River at Saratoga will remain
in effect until further notice. The slow rise to the river has
leveled out this afternoon with another brief rise expected late
tonight. The river should remain near flood stage over the next 36
hours before the next Pacific system moves into the area. Another
round of widespread rainfall, thunderstorms, and cooler
temperatures are expected. However, high elevation snow melt will
be limited this weekend due to temperatures near freezing along
with an additional chance for accumulating snow above 9000 feet.
So any flooding concerns around the upper North Platte, Encampment
river, and Laramie river will have to result from mostly moderate
to heavy rainfall.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Watch from 6 PM MDT this evening through Thursday
evening for WYZ110.
NE...None.
&&
$$
SHORT TERM...TJT
LONG TERM...JSA
AVIATION...WM
FIRE WEATHER...TJT
HYDROLOGY...TJT
Area Forecast Discussion
National Weather Service Des Moines IA
632 PM CDT Wed Jun 19 2019
...Updated for 00z Aviation Discussion...
.DISCUSSION.../Tonight through Wednesday/
Issued at 410 PM CDT Wed Jun 19 2019
Several concerns over the next couple of days with an active
weather pattern develops and the potential for severe storms and
heavy rain exist Thursday into the weekend. Leaned towards a
blend of the HRRR/HREF/NAM tonight into Thursday and then a
GFS/ECMWF blend for Friday into Saturday.
Tonight...lingering light showers and possibly a brief
thunderstorms remain possible across the southeast early this
evening. Weak high pressure and subsidence builds into the state
late this evening into Thursday morning allowing for some patchy
fog to develop over the central and southern sections of the
forecast area. The hires models are suggesting visibility to range
from 1-3 miles overnight but not completely widespread. Still,
with the dewpoint depression less than 3F and near 0F in most
areas and light winds and plenty of low level moisture hanging
around from the rain, confident to see at least the patchy fog.
Thursday into Saturday...The synoptic setup on Thursday has
shifted further east and the potential for severe weather has
increased across the western part of forecast area. First, there
is a subtle shortwave embedded within the upper level ridging
during the day Thursday. This may spawn a few showers/storms as it
progresses eastward during the late morning into the early
afternoon Thursday. The latest HRRR/ARW/NAM suggest this trend,
but the forcing wanes as it moves east and thus, have low
confidence of anything making east of I-35 attm and kept the
forecast dry for now.
The main focus tomorrow was on the next stronger shortwave to
provide the potential for severe storms over western (and maybe
central) Iowa by the late afternoon into the evening. The 19.12z
HREF and 19.12z HRRR depict storms to track across the southwest
past 22z Thursday. However, the 19.18z HRRR suggest the storm
activity further northeast. The instability axis is basically the
Nebraska/Iowa border or slightly east past 21z Thursday in
southwest Iowa. MUCAPE increases to 2500-5000 J/kg across the
southwest Thursday afternoon and forcing is fairly potent with the
second shortwave. CSQ (NAM/GFS) hodographs are nearly sickle
shape and should be enough shear to provide rotating updrafts.
LCLs lower to around 500m by the afternoon into the evening and
the best window for tornadic activity looks to be from around 21z
Thursday to 02z Friday. However, the hail and damaging wind threat
is a bit higher. The storms are likely to quickly diminish past
02z Friday as they move east since the instability and forcing
weakens. Again, the severe threats include all modes, especially
with the amount of instability present. Certainly there is the
potential for a couple supercells to get going with rotating
updrafts Thursday afternoon and evening.
Next up is the possibility for convection Friday morning. There
remains discrepancies wrt to where the boundary lays up across the
state as well as the timing between the models. Thus, low
confidence in the forecast past 06z Friday into Friday afternoon.
More concerned about the overnight convection Friday night into
Saturday morning across the forecast area. The 19.12z ECMWF and
even the GFS suggest the LLJ to increase and spawn widespread
storms over the CWA past 03z Saturday. Plenty of instability
present and impressive moisture transport continues to feed into
the state Friday night. Warm layer cloud depths are around 4000m
b/t 03-12z Saturday and precipitable water values range from 1.5
to near 2 inches which is near the climatological max for this
time of year per OAX sounding. Certainly concerned with the onset
of convection for severe weather, but also the heavy rain threat
leading to flooding across the area by Saturday morning.
Saturday through Wednesday...The active weather pattern continues
over the weekend into Monday. The region begins to turn into more
southwest flow aloft and there is another shortwave to bring
storms late Saturday night into Sunday. Main threat with this
shortwave is more heavy rain as warm layer cloud depths range from
3500-4000m, PWATs range near 2 inches, and decent moisture
transport vectors into the state b/t 06-12z Sunday. Should be a
break in the convection during the day Sunday before a strong
shortwave trough tracks across Nebraska Sunday night into Monday
and brings more storm chances to the forecast area during this
time. There appears to be a little time for instability to rebound
Sunday afternoon before the shortwave quickly moves across the
state by the evening. Yet something to monitor for severe weather
potential and heavy rain across the forecast area.
&&
.AVIATION.../For the 00Z TAFS through 00Z Thursday evening/
Issued at 632 PM CDT Wed Jun 19 2019
Mainly VFR showers will wane over the next few hours over southern
Iowa lingering the longest at OTM. Light winds and recent rains
should foster fog development after midnight with high confidence
in at least MVFR visibilities with some hints of IFR or lower
visibilities briefly at DSM and OTM. Will reserve those
visibilities should they be needed for the 6z TAF issuance. As fog
dissipates a few hours after sunrise, VFR conditions are expected
through the end of the period.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...Podrazik
AVIATION...Ansorge
Area Forecast Discussion
National Weather Service Quad Cities IA IL
853 PM CDT Wed Jun 19 2019
...HYDROLOGY AND UPDATE...
.UPDATE...
Issued at 846 PM CDT Wed Jun 19 2019
Rain tapering off along the Mississippi and will continue to
gradually exit IL counties through Midnight. Threat for
widespread heavy rain and flash flooding has diminished in the
south, and have therefore cancelled the flash flood watch.
&&
.SYNOPSIS...
Issued at 330 PM CDT Wed Jun 19 2019
A weak cold front slowly moved through the area today. Dewpoints
in the 50s were reported behind the front with dewpoints in the
60s in front of it. Aloft, a shortwave was translating through the
flow across this area of baroclinicity. This wave lead to the
development of showers and storms across the area this morning and
again this afternoon. In fact some flash flooding was reported
across the far southern CWA early this afternoon.
&&
.SHORT TERM...(This Evening through Thursday)
ISSUED AT 330 PM CDT Wed Jun 19 2019
Active short term period as the upper level wave is expected to
pivot across the area through the next 12 hours or so. Issued a
flash flood watch earlier on the shift with a slow moving storm
into the area. Convection is forming back to the southwest over
MO. That airmass will eventually advect into the southwest CWA and
may lead to some thunderstorms. The HRRR and the other hires
models keep the strongest convection south of the CWA tonight,
which would be good for our southern tier. However with the nearly
saturated grounds across the area, will keep the FFA going as only
a little rain will cause flooding again.
What is rather interesting is that heating across northern Iowa
is leading to some instability. I believe some thunderstorms will
form across the northern periphery of the rain shield. The HRRR
and to some extent the NAMnest shows this as well. Overall,
heaviest precip will fall along and south of an axis from Memphis
to Princeton tonight. No severe weather is expected from and of
these storms across our area due to limited solar insolation.
Overall most of the area will be wet and cool.
Thursday looks to be a great day across the area with lower
humidity and highs in the 70s. The sun will eventually start to
peak out across the area.
.LONG TERM...(Thursday night through next Wednesday)
ISSUED AT 330 PM CDT Wed Jun 19 2019
Thursday night...Upper ridge will look to press eastward and sharpen
up along and west of the MS RVR Valley by Friday morning. Most of
the 12z run models are less bullish about it, but still feel an
elevated wing/band of showers and thunderstorms may form later at
night on nose of a nocturnal southwesterly LLJ. Banking on some WAA
AC and increasing southeast winds will go with lows in the upper 50s
to lower 60s, with some mid 60s in the south.
Friday...Assessing the latest model vertical profiles, they really
build a EML/capping warm wedge aloft centered between a H85-H7 MB
layer. This may really limit sfc based convection until at night.
But a few solutions linger some elevated showers/storms out of Thu
night into Friday morning, with possible more elevated sctrd showers
and possible storms during the afternoon. The models are now not as
warm under the inversion, and elevated debris clouds may also make
fcst temps in the low to mid 80s along and south of I80 a bit hard
to attain. Fcst soundings also limit mixing depth and have sfc-based
convective temps over 90. This may make much of the afternoon mainly
dry, and lower SB CAPEs than what previous models indicated. MCS-
forcing tool suggests convective spawning grounds will look to take
off over the MO RVR Valley into central IA Friday evening, with a
resultant MCS propagating east acrs the local area later Friday
night. With the main sfc boundary possibly staying anchored along
the IA/MO border draping into southeastern IL, any incoming MCS may
be mainly elevated. Unless it can become sfc rooted to the south,
the severe threat may be more limited to hail or wet microburst
winds. Heavy rain will be a threat with high THTA-E being feed into
the system by a southwesterly 30-40 KT LLJ, with flash flooding
potential growing especially acrs areas recently hit by heavy rain.
Saturday and Sunday...This a period where convection from the day
and especially night before affects what happens the following day.
Where resultant outflow boundaries lay out for refocus for storm
development, and how fast or slow cloud/precip debris lingers into
the day limiting heating/instability build up. In general for Sat,
after whatever morning debris can clear, the latest medium range
models maintain thermal ridge in place overhead. If we can get
recovery and some afternoon sunshine, ambient temps may warm into
the mid to upper 80s with sfc DPTs near the upper 60s or around 70.
Thus a higher CAPE build up, but fcst soundings show more elevated
mixed layer(EML)capping possibly keeping a lid on things until later
Sat evening or night. Where evening or nocturnal convective
complexes can fire on periphery of the ridge and helped by vort
max`s or upstream MCV moving into a renewed LLJ feed, is still
uncertain. They may fire overhead Sat evening like the ECMWF
suggests, or more to the north and west with just some sctrd
elevated showers/storms like the 12z GFS suggests. Will have to keep
rather high POPS going especially for the night periods all weekend,
with more heavy rain possible if we take another MCS hit. Sunday
more muddled but potentially stormy during the day and night if
upstream upper level trof tries to battle it`s way east and nudge
the thermal ridge off toward the GRT LKS. More heavy rain and severe
weather possible in or near the area Sunday and Sunday night
depending on where this wave concentrates convective clusters or
systems.
Monday through next Wednesday...Scattered showers and a few storms
look possible on Monday under the passing upper trof, then maybe a
break in the wake of this system as the next thermal ridge builds
acrs the plains. But the region may not be totally dry as sctrd
storm clusters may fire in pattern transition in elevated warming
return flow especially at night somewhere acrs the midwest. Temps
will generally look to be warm next week in the 80s from Tuesday
on.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
ISSUED AT 639 PM CDT Wed Jun 19 2019
Rain with bouts of MVFR to IFR conditions will continue to taper
off from NW to SE across the terminals this evening. Some
partial clearing is possible mainly at DBQ and CID overnight,
which if occurs could lead to some fog and IFR conditions. Not
confident on this, and for now leaned toward consensus of guidance
advertising generally MVFR ceilings developing post rain at all
sites in cooler north winds into Thursday AM, lifting to VFR based
stratocu by afternoon.
&&
.HYDROLOGY...
Issued at 846 PM CDT Wed Jun 19 2019
Recent heavy rainfall has led to some minor rises on the
Mississippi downstream of Burlington. The rise is just enough to
nudge Gregory Landing back above moderate flood stage over the
next 12 hours, thus a warning has been issued for the change in
category. Otherwise, heavier rain earlier is resulting in just
some within bank rises on several tribs in far southeast Iowa,
northeast Missouri and west central Illinois.
Previous discussion Issued at 1210 PM CDT Wed Jun 19 2019
The Mississippi River continues a general fall trend at most sites,
and should continue into the start of the weekend. The exception is
at LD19 at Keokuk and Gregory Landing where locally heavy rain
and run-off is producing a small bump up in river levels there.
It will start falling again by tonight after the rain lets up.
Other sites from Rock Island LD15 on down to Keithsburg have
either finally dropped below flood stage, or dropped out of
moderate into minor flood category over the past 18-24 hours. Will
have to watch for rising trends on portions of the La Moine, Fox,
Des Moines, and lower Skunk Rivers this afternoon in response to
ongoing bands of heavy rain moving north across southeast IA,
northeast MO and west central IL today.
Looking ahead, the pattern still appears will become more summer-
like and active with periodic rounds of heavy rain producing
thunderstorms by the weekend. While it is still too early to
determine exact rainfall amounts and where the heavy swaths may lay
out, the coming synoptic pattern suggests the potential for
occasional rounds heavy rainfall which may cause rises again on some
of the rivers, or at least slowing or stalling the current falling
river trends. This includes portions of the mainstem Mississippi
River, where sites such as LD15 in the Quad Cities and LD16 IL City
which have recently just slipped under the flood stage, may
experience new rises and possibly near their respective flood stages
again by early next week. Stay tuned for later river forecasts and
trends through the weekend.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...McClure
SYNOPSIS...Gibbs
SHORT TERM...Gibbs
LONG TERM...12
AVIATION...McClure
HYDROLOGY...McClure
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
625 PM CDT Wed Jun 19 2019
.Discussion...
Issued at 324 PM CDT WED JUN 19 2019
Message of the day: Rain chances continue through the evening
hours, mainly east of I-35. Moderate to heavy rainfall is
expected in northeast MO, with another inch or so of rain
possible.
A shortwave trough and surface low have been taking their time
moving through the area today. This has kept the shower and storm
chances lingering throughout the day today. The best chance for rain
and is in northeast MO. An area of showers has already
redeveloped on the nose of a strengthening (albeit still weak) LLJ
and will slowly move through northeast MO this afternoon and
evening. No severe weather is expected in this area, but moderate
to heavy rain is a concern. PWAT values are around 1.6- 1.7 which
is well above normal. As a result, another inch of rain is
possible across northeast MO today, on top of the 1-2 inches that
already fell this morning. Therefore, a flash flood watch has been
issued for Chariton, Linn, Schuyler, Adair, Macon, and Randolph
county in MO. Remember if approaching a flooded roadway, to turn
around don`t drown. Additional rain development with isolated
thunder in central MO is also expected today. No severe weather is
expected with this activity.
High pressure will build in tonight, with the center of the high
over the area around sunrise. The calm to light winds and moisture
near the surface will likely result in patchy fog across the area
in the morning, with more dense fog possible in northeast MO. Any
fog that develop should diminish not long after sunrise.
The high pressure will move out quickly Thursday, with a surface
low on its heels. In the upper levels, we will be under a weak ridge
with energy ejecting into the upper Midwest from a closed low over
the northwest U.S. Right now, the surface low looks to move
northeast through central KS into northeast KS/southeast NE. This
will result in a southwest to northeast oriented cold front just to
our west and a west to east oriented warm front across our northern
counties. As for the upper level support, it appears a subtle
shortwave trough will move through over our northern counties,
though the better upper level support will remain well north of MO
and KS on Thursday. The 15Z HRRR and RAP, as well as the NAMNest,
NAM, and GFS all depict isolated storm development in northwest MO
and northeast KS in the late afternoon and early evening Thursday.
The environment is this area is also supportive of strong to
severe storms. CAPE values will approach 4000 J/kg with 0-6 km
shear around 40 kts and steep low-level lapse rates. While
damaging winds and large hail are the main concerns, can`t
completely rule out an isolated tornado or two with the warm front
in close proximity, low LCL heights, SRH around 150 m2/s2, and
0-1 km shear around 15 kts. The main limiting severe weather factor
to keep in mind though is heights will generally be rising in the
upper levels.
Thursday night into Friday morning, a more robust shortwave trough
will eject east from the main upper level low to our northwest,
with the surface low and associated boundaries essentially
stalling across the region. The LLJ should strengthen, helping
develop an MCS that should make it to our area Friday morning
around sunrise. However, the Canadian and ECMWF want to move the
MCS north of the area. Will have to monitor future runs to see if
a greater consensus is reached among the models. If the MCS does
move into the area though, damaging winds will be the main
concern, but can`t rule out large hail and an isolated tornado. A
favorable environment for severe weather could continue into
Friday afternoon and evening, mainly north of I-70; however, that
will depend on morning activity and resultant boundaries and if we
can destabilize. If we can get storm development Friday afternoon,
all modes of severe weather will be possible.
Friday and Saturday temperatures are, for the first time for many
areas, forecast to reach 90 degrees. Dew points will also be high,
the upper 60s to low 70s, helping heat indices reach the mid to
upper 90s across the area. Given that this is the first time this
year we are expected to experience the summer heat, care needs to be
taken when doing outdoor work/activities. Make sure to drink plenty
of water and take frequent breaks.
Storm chances will continue through the weekend, until the
aforementioned upper level low finally moves through the central
U.S., helping move the surface low and cold front through the
region. This will provide a break from storm chances and relief
from the above normal temperatures.
&&
.Aviation...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 625 PM CDT WED JUN 19 2019
Lowest few stratocu decks will scatter out over the next few
hours, ending rain shower chances and effectively raising
ceilings, then eventually resulting in clear skies overnight.
Surface high pressure will move over by sunrise, possibly allowing
patchy fog to develop at/near terminals during the morning hours.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...Flash Flood Watch through Thursday morning for MOZ008-017-024-
025-032-033.
&&
$$
Discussion...Grana
Aviation...Laflin
AREA FORECAST DISCUSSION
National Weather Service Sioux Falls SD
1035 PM CDT Wed Jun 19 2019
.SHORT TERM...(This Evening through Thursday)
Issued at 347 PM CDT Wed Jun 19 2019
Shortwave diving into eastern South Dakota this evening will
continue to produce widely scattered showers or sprinkles mainly
across southeast SD. High res models such as the HRRR and ARW have
also started to point towards additional scattered showers and
thunderstorms forming late afternoon and this evening in south
central along the low level frontal boundary. Shear is expected to
continue to increase this evening in south central, however with
cloudy skies today, instability is limited. Model soundings depict
elongated, skinny elevated CAPE values of around 500 to 1000 J/KG.
Could see a few stronger storms with small hail and gusty winds, but
the overall severe threat is low. One thing to watch: given the
earlier reports of a landspout with this activity in Todd County,
will need to watch for pockets of low level vorticity along the
boundary as it moves into our western border. Landspout threat
overall is very low.
Shortly after sunset, models weaken any thunderstorm activity, with
a few isolated showers and storms remaining possible in southeast SD
into the early morning hours. Last tonight a stronger wave tracks
eastward across the Dakotas, bringing a better threat for showers
and thunderstorms late tonight through the day on Thursday. Activity
will be mainly focused west of I-29 in the morning, and to the east
midday into the afternoon. Strong shear and weak to modest elevated
instability will keep a marginal threat for strong or severe storms
in the morning. Instability increases in the afternoon in northwest
Iowa and northeast Nebraska which could materialize to a greater
threat for afternoon severe storms with hail to the size of half
dollars and wind gusts to 65 mph as the main threat.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 347 PM CDT Wed Jun 19 2019
Active summertime weather pattern will direct several waves into the
region headed into early next week as the upper pattern shifts
towards southwest flow. Very slow moving upper level trough digs
southward into the Great Basin Thursday night and Friday, stalling
over the Intermountain west this weekend.
For Thursday night, the next shortwave lifts across the northern
Plains, with a warm frontal boundary potentially serving as the
catalyst for the next severe threat. Mid level warm air advection
however will surge northward into the I-29 corridor and eastward
late Thursday night into Friday. The main concern will be the
location of the surface and elevated boundaries and how the ongoing
convection Thursday night into Friday will impact these boundary.
Steep mid level lapse rates (8+), CAPE values greater than 2000
j/kg and bulk shear values greater than 40 kts will be possible
south of the warm front in the afternoon, but the question will be
how far north this front reaches and whether convection earlier
in the day/overnight will impact profiles. If conditions become
maximized, large hail, and damaging winds will be possible across
mainly the eastern half of the forecast area. Cannot rule out an
isolated tornadic threat near the warm front as well if surface
based storms develop. In less optimal conditions with limited
instability and without the boundary interaction, elevated
stronger or marginally severe storms are expected.
Additional scattered showers and storms continue overnight Friday
into Saturday morning, lingering into the afternoon east of I-29.
The next wave lift into the central High Plains on Sunday, with yet
more scattered showers and thunderstorms lifting northward through
the region.
Early next week northwest flow aloft transitions to a more zonal or
weak ridging pattern, however models show some fairly significant
timing differences. The pattern should bring warmer temperatures
along with much lower precipitation chances.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1033 PM CDT Wed Jun 19 2019
The main concern for aviation interests will be with the
increasing risk for thunderstorms after midnight and through
Thursday morning. A linear band of showers and embedded
thunderstorms will move eastward through mid-day bringing with
them short periods of reduced visibility and a westerly wind
shift.
Some widely scattered afternoon redevelopment could be possible
especially across areas of NW Iowa, but coverage low enough to
hold off on any mention in this TAF.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...Dux
Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
638 PM CDT Wed Jun 19 2019
.AVIATION...
/00Z TAFs/
...INCREASING CONVECTIVE COVERAGE LIKELY ACROSS D10 TRACON WITHIN
NEXT FEW HOURS...
TS have erupted this evening to the E and NE of the D10 TRACON.
With tops to over 60 kft...major impacts are underway to the
Bonham arrival gate. Expect these TS to continue tracking towards
the ESE with time...resulting in continued impacts to the Bonham
arrival gate as well as increasing impacts to eastbound
departures.
Closer to the Metroplex TAF sites...convection has struggled to
develop where a small capping inversion remains apparent on the
00Z RAOB. Water vapor satellite imagery shows mid-level ascent
increasing across the Big Country however...which should spread
E-NE with time. It is still expected that TS should develop
within the D10 TRACON during the next few hours...with TEMPO +TSRA
possible at all terminals. Given the large instability and wind
shear in place...any TS will be capable of wind gusts in excess of
50 KT as well as GS/GR. There remains some uncertainty with
regards to the amount of coverage this evening...but the HRRR
(which seems to have the best handle on the ongoing convection)
has been consistent with some degree of convective coverage over
the Metroplex between roughly 02Z and 04Z...with convection likely
moving out by 06Z.
To the south at KACT...the picture is a little unclear. The HRRR
does suggest that some TS will be possible near KACT late this
evening...but confidence is too low to include any TEMPO groups at
this time.
For all TAF sites...amendments will be possible if not likely over
the next few hours as radar/satellite trends are monitored.
37
&&
.SHORT TERM... /Issued 324 PM CDT Wed Jun 19 2019/
/Through Tonight/
Key Messages:
-Thunderstorms are expected to begin developing, initially
northeast of the Dallas/Fort Worth Metropolitan Area, after 4:00
PM this afternoon.
-Thunderstorms will continue to develop back to the southwest,
with the highest storm chances expected in the Metroplex after
7:00 PM.
-Some severe thunderstorms are likely, with large hail (perhaps
greater than two inches in diameter) and damaging wind gusts in
excess of 60 MPH being the main hazards.
-A tornado threat will exist as well, with the greatest tornado
threat expected to exist from 5-8 PM, generally near and
northeast of Dallas.
-While significant flash flooding is unlikely, some localized
flooding may be possible in urban areas.
The main story for the short-term forecast will be the convective
chances (and severe weather chances) through the period. At
present time, a 1007 mb surface low is located over West Texas,
with a cold front running back to the northeast across Oklahoma
and into the Missouri River Valley. A dryline extends from the
surface low back to the southwest towards Big Bend National Park.
The warm sector is characterized by a very warm, moist, and
unstable air mass. As of this writing, DFW is 91/75 and Waco is a
sweltering 95/75. While these temperatures and dewpoints are not
entirely atypical for mid June in North and Central Texas, what is
unusual is that per the special 19Z RAOB out of Fort Worth, very
steep mid-level lapse rates are present (8.5 C/km). The result of
this combination is a highly unstable air mass with MLCAPE values
approaching 4000 J/kg. Upper-level flow is impressive too, with
effective bulk shear values approaching 60 KT on the 19Z RAOB.
High-resolution model guidance is in good agreement that
convection should initiate over our northeastern counties to
begin, probably some time between 4 p.m. and 6 p.m. Storms should
begin to the northeast of DFW, and then back-build to the
southwest through the evening. The most likely time for
thunderstorms in the core of the Metroplex (i.e. Collin, Dallas,
Denton, and Tarrant) will be probably be after 7 p.m.
Thunderstorms should progress southeast through the evening, and
should taper off after 3 a.m.
Given the aforementioned high levels of instability and strong
wind shear, any thunderstorms that develop will likely become
severe. Steep mid-level lapse rates and large instability will
result in a risk for large hail (with significant hail, i.e.
larger than two inches in diameter, not out of the question). With
time, shear vectors oriented nearly parallel to the approaching
cold front should allow convection to grow upscale into a
mesoscale convective system (MCS). While the large hail threat
will likely continue, a damaging wind threat will exist as well.
Severe wind gusts in excess of 60 MPH will be likely in the
stronger convective cores. Finally, with regards to the tornado
potential, instability is actually a bit limited in the lowest 3
km of the atmosphere, and low-level flow is not particularly
strong, both of which may limit the tornado potential. With that
being said, total instability is very strong, and deep layer
shear is certainly high enough to support some rotating
thunderstorms, particularly during the initial phases while
thunderstorms remain somewhat discrete.
With regards to heavy rain potential, precipitable water values on
the 19Z sounding were around 1.65 inches, which is not
particularly impressive, but sufficient enough to result in heavy
rainfall in the more intense convective cores. Storms should also
move at a fairly decent speed (30+ MPH) limiting the potential for
widespread flash flooding. Having said that, if we were to get any
training of thunderstorms, particularly over urban areas, a
localized flooding threat could develop.
Finally, into Central Texas, thunderstorm activity may be more
limited, but some isolated to widely scattered storms may still be
possible late this evening. Because of concerns regarding
coverage, the severe weather threat will be lower here, but any
storms that do develop will have to the potential to become
severe.
37
&&
.LONG TERM... /Issued 324 PM CDT Wed Jun 19 2019/
/Thursday and beyond/
Summary: Hot and humid conditions will continue to be of concern
through the end of the week. Low thunderstorm chances will also
continue through early next week, but not everyone will see rain
each day. The best chances will be Sunday into Monday.
Most of the region will be rain-free on Thursday, but the far
western counties will have a low potential for thunderstorms.
Both the GFS and ECMWF are hinting at the dryline across the Big
Country bulging far enough eastward to where thunderstorms may
develop and affect the far western counties Thursday afternoon.
Model soundings reveal a mostly capped environment, but given the
hot afternoon temperatures, a downburst wind threat will exist if
thunderstorms do initiate along the dryline. With 850 mb
temperatures in excess of 25C across the region, afternoon
temperatures will range from the mid 90s along the Red River to
near or just above the century mark across the west. The hot
temperatures, in combination with dewpoint values in the low to
mid 70s, will have heat index values ranging from 104 to 110, with
the highest values being across Central Texas. A limiting factor
on whether the higher values will be reached or exceeded is the
evolution of convection from Wednesday evening... so the Heat
Advisory will remain confined across the southeastern counties.
Weak disturbances will track across the region as an upper level
trough deepens across the western US, and in combination with
ample moisture, there may be scattered thunderstorms on Friday
and Saturday. Friday will feature another hot and humid day with
high temperatures similar to Thursday, and may necessitate a Heat
Advisory. The best chances for showers and thunderstorms will be
Sunday into Monday as a shortwave tracks east across the Central
Plains. Guidance has hinted at a weak front being an area of
focus for convection across Oklahoma, which may slide south
towards North Texas Sunday night. Mid week rain chances may start
to wind down as upper level ridging sets up across the west.
Otherwise, highs will be in the low to mid 90s this weekend and
early next week.
Garcia
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 74 97 77 96 77 / 60 10 10 0 20
Waco 75 99 77 98 77 / 40 5 5 0 10
Paris 71 92 75 92 76 / 80 10 10 5 10
Denton 71 97 77 95 77 / 60 10 10 5 20
McKinney 71 96 77 95 77 / 80 10 10 0 10
Dallas 75 97 77 96 78 / 60 10 10 0 20
Terrell 74 97 77 96 77 / 60 5 10 0 10
Corsicana 75 95 76 93 76 / 60 5 5 0 10
Temple 74 99 77 98 77 / 40 10 10 5 10
Mineral Wells 70 99 75 96 75 / 50 10 10 5 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT Thursday for TXZ135-146>148-157>162-
174-175.
&&
$$
37/25
Area Forecast Discussion
National Weather Service Hastings NE
641 PM CDT Wed Jun 19 2019
.SHORT TERM...(This evening through Thursday)
Issued at 252 PM CDT Wed Jun 19 2019
Aloft: Animations of RAP tropopause analyses and G16 WV imgry
showed a wk trof over the Cntrl USA. The trof axis extended from
Cntrl NEB into Wrn KS. Upstream...the low that has been over the
Aleutians has mvd into SW Canada as fcst and it has a strong 130
kt jet streak associated with it. This low will remain over SW
Canada thru tomorrow. Meanwhile...a couple of shrtwv trof will
rotate S of the low helping to carve out a broad trof over the Wrn
USA. The 1st trof is currently over WA/ID. This trof will mv acrs
Srn SD and Nrn NEB tonight.
Surface: A wk stationary front extended from the GtLks down to
the Srn Plns and was no factor here. Low pres was over Srn AB. Its
associated cool front extended SW thru the Pac NW. This front
will mv E tonight and emerge into the Dakota`s and Wrn NEB by
12Z/Thu. This front will weaken and dissipate as is crosses the
CWA tomorrow AM. Very wk high pres will then build over NEB in the
afternoon.
Rest of this aftn: Small/spotty shwrs hv been mvg thru ahead of
the upr trof axis. Can`t rule out an isold tstm...mainly W of Hwy
281 where more insolation has occurred...allowing for greater
potential instability.
Tonight: A lone tstm or two could dvlp over the Sandhills and
early this eve and meander into the CWA W of Hwy 281...or even W
of Hwy 183. Otherwise a quiet evng and night most locations. Sct
tstms will dvlp over SD associated with the aprchg trof and LFQ of
the upr- lvl jet streak. There is a slight chance the Srn tail of
these storms could extend into cntrl NEB and brush the Nrn fringe
of the CWA well after midnight.
Decided at the last min to include some patchy fog in the fcst.
Lots of low-lvl mstr remains and good radiating will occur with
light winds. Don`t expect it to get bad as winds will be
gradually picking up toward dawn...but with low temp/dwpt spreads
this aftn it won`t take much for some fog to form.
Near normal temps.
These will be high based (10K ft). Fcst soundings only show about
500 J/kg of elevated CAPE. So no svr tstms are expected.
Thu: A couple of tstms could linger N and E of GRI during the AM.
Elevated CAPE will be about the same. So no svr tstms expected.
Otherwise...mostly sunny and dry as a shrtwv rdg builds overhead
with NVA. RAP/NAM/GFS soundings show substantial CIN.
Near normal temps.
.LONG TERM...(Thursday night through Wednesday)
Issued at 252 PM CDT Wed Jun 19 2019
Aloft: The last 2 UKMET/EC/GFS-FV3/CMC runs are tightly-
clustered on a longwave trof progressing thru the Wrn USA Fri-
Sat...anchored by the low ovr SW Canada that will be mvg into the
Canadian Prairies. By Sun the Wrn trof will be aprchg the Plns and
will cross NEB/KS Sun night...but with decreased potency/lower
amplitude. Retrogression of the longwaves will occur Mon-Wed as
the next low of the GlfAK is fcst to drop S and remain just off
the W coast. That will mean rising heights/thicknesses here Mon-
Wed as a longwave rdg builds ovr the Plns.
Surface: A potent shrtwv trof will induce a sfc low to form ovr
WY Thu night. This low will occlude into MT Fri with its cool
front crossing the CWA. This front will clear the CWA by just
barely. It will stall just to the S and E as it becomes parallel
to the SW flow aloft. As the upr trof aprchs...a sfc low should
form on the front and mv NE along it Sun. Then quiet as high pres
builds in and return flow dvlps.
Temps: Near normal Fri then a little cooler than normal Sat-Mon.
Tue-Wed temps should climb a little abv normal.
Tstms: Lots of uncertainty with the sys Thu night into Fri. Stg
WAA will be occurring at the nose of the low-lvl jet with the cool
front mvg in...but lack of forcing aloft results in very poor mdl
agreement on QPFs. This is due to a plume of very warm mid-lvl
temps (stg cap) advecting over the CWA Thu night (700 mb temps
12-15C). Believe the most likely scenario is that tstms will form
along the cool front (well NW of the CWA) Thu night and cont mvg E
thru the Sandhills Fri AM...at the Nrn edge of the cap. Some of
this activity could brush the Nrn CWA (N of I-80). That may be it
for the CWA. The front is fcst to be exiting the CWA by peak
heating and it is probable the cap will keep any tstms from
forming Fri aftn.
Can`t entirely rule out a couple tstms Sat...but the next best
shot will be Sun as the upr trof mvs in. The CWA will be on the
cool side of the front. So instability will probably insufficient
for any svr tstms. Then mostly dry Mon-Wed.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday)
Issued at 641 PM CDT Wed Jun 19 2019
Scattered showers have exited to the east and scattered cumulus
clouds have risen to VFR and are diminishing in coverage. Skies
are expected to be mostly clear. Light winds are expected
overnight and some patchy fog is possible with the recent rain and
light winds. MVFR conditions are possible during the early morning
hours to near sunrise. This is expected to diminish near sunrise
with increasing southerly winds. A front will move through the
region Thursday afternoon causing winds to become northwesterly
and breezy.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Kelley
LONG TERM...Kelley
AVIATION...Billings Wright
Area Forecast Discussion
National Weather Service Huntsville AL
928 PM CDT Wed Jun 19 2019
.NEAR TERM...(Tonight)
Issued at 928 PM CDT Wed Jun 19 2019
A line of strong to severe thunderstorms on-going over Middle
Tennessee approximately halfway between Kentucky and Alabama, and
mostly just east of I-65. This activity continued to track a bit
south of due east. An outflow boundary created by this convection
will move southward, bisecting parts of the Tennessee Valley in the
late evening and overnight. Another area of strong and severe
convection continued to develop and expand over the OK-TX-AR region.
Some of this activity has moved rather quickly to the east, now
moving over south central and SE Arkansas. Other strong and severe
storms continued near the NE TX/SE OK border, and SE of Abilene.
Quiet weather currently prevailed over the greater Tennessee Valley,
with 9 PM temperatures still very warm in the mid 70s to lower 80s,
with dewpoints in the 70-75 degree range. Benign conditions will
begin changing after midnight, as effects from convection over the
Southern Plains nears the region. Output from the most recent
Convective Allowing Models - CAM, HRRR, ARW-NMM/ARW all indicate that
storms to our west will begin impacting NW Alabama in the 20/0800Z
timeframe, with the storms moving eastward across the remainder of
the area during the course of daybreak Thursday. The RAP and even
more so the new NAM were weaker with the convection as it headed this
way.
Forecast wise, will stay more towards the CAM solutions, that will
bring scattered to numerous thunderstorms in the late night. Per the
SPC Day-1 forecast, think the stronger storms will be more towards
the west, with a weaker trend to the east. If the storms interact
with the above noted boundary from convection over TN, enough lower
level shear realized could help with rotating storms; thus cannot
totally rule out a tornado or two. Damaging wind gusts is the main
threat posed by the stronger and/or severe storms. Wet-bulb zero
heights in the 12K` ASL range should help limit severe hail, but
will not totally rule it out in the stronger storms. May add a few
T+ to our western areas late tonight with the arrival of the
convection. The overall forecast otherwise was in good shape.
.SHORT TERM...(Tonight through Friday night)
Issued at 259 PM CDT Wed Jun 19 2019
The NAM12 and other convective models have come into better agreement
that a longwave trough axis will drop southeast toward northern
Alabama and southern middle Tennessee late tonight. Good bulk shear
parameters between 30 and 45 knots, ample instability, and low
level helicity around 200 m2/s2 show up in model guidance ahead of
this system. As this trough axis swings eastward from Kansas and
Missouri into the Tennessee Valley after midnight, clusters of strong
to severe thunderstorms are expected to develop ahead of it. Wet-
bulb heights, freezing levels, and mid-level lapse rates look fairly
benign for larger hail development. Could see some smaller hail
though. Main timeframe for the strong to severe activity looks to be
from around midnight to 8 AM. Main threats would be damaging winds.
Isolated severe thunderstorm activity could linger into the mid
morning hours in eastern sections of northern Alabama.
Shear does weaken during the day on Thursday as the trough axis
continues to shift southeast of the area. Could still see a few
isolated strong to marginally severe storms near and south of a line
from Huntsville to Moulton areas into the afternoon hours. However,
believe most of this will occur in central and southern Alabama and
into Georgia. Could see some locally heavy rainfall with this system
(mainly through the early to mid morning hours). Isolated flash
flooding is possible, but flooding impacts overall are not expected
to be very widespread.
Latest model suites show the upper wave lifting northeastward into
the northeastern states Thursday evening with its trailing front
settling southward into southern Alabama/Georgia. This should end any
lingering isolated precipitation chances by before midnight over
northern Alabama and southern middle Tennessee. Some guidance moves
the trailing front northward into northern Alabama as a warm front
during the day on Friday. Included isolated shower and thunderstorm
chances near this boundary. With a much stronger upper ridge over
the area and more abundant sunshine expected, it should be noticeably
warmer with highs reaching the lower 90s at least.
.LONG TERM...(Friday night through Tuesday)
Issued at 259 PM CDT Wed Jun 19 2019
This activity should dissipate Friday night with very warm overnight
temperatures continuing to be in the lower 70s.
This overall pattern changes little trough the weekend. Highs in the
lower to mid 90s look feasible, but at this point stayed on the lower
end of that range. Periodic isolated to scattered diurnally driven
shower and thunderstorm chances may be possible within the upper
ridging, as the convective activity dives southeast from Kentucky
into the Carolinas, possibly re-enforcing a weak area of convergence
with the upper ridge over northern Alabama.
Early next week looks more interesting and unsettled as guidance
hints at another stronger front pushing into the area. Higher
precipitation chances are in the forecast Monday and Tuesday as a
result. Cooler daytime highs in the mid 80s to around 90 degrees are
expected with the increased cloud cover and precipitation.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 704 PM CDT Wed Jun 19 2019
VFR weather should continue this evening over the Tennessee Valley.
Surface high pressure situated SE of the region will provide SW winds
in the 10kt range. An area of strong/severe convection across the
TX-OK-AR region will move eastward during the course of the evening.
It should begin impacting this area after midnight. The stronger
convection should begin impacting KMSL ~08Z and KHSV ~10Z. Gusty
winds over 25kt, along with reduced VIS/CIG due to heavy rains are
expected. The heaviest showers should end a couple of hours after
commencing, with MVFR CIGs persisting into the mid/late morning. VFR
weather should return by the early afternoon. SW winds in the 10-15kt
range for much of the overnight, should become WSW and increase into
the 15-20kt range with some higher gusts Thu afternoon.
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$
NEAR TERM...RSB
SHORT TERM...KTW
LONG TERM...KTW
AVIATION...RSB
For more information please visit our website
at weather.gov/huntsville.
Area Forecast Discussion...UPDATED
National Weather Service Little Rock AR
628 PM CDT Wed Jun 19 2019
.DISCUSSION...
Updated to include the 00Z aviation discussion below...
&&
.AVIATION...
Chances for SHRA/TSRA will be highest at the central and SRN
terminals this evening into the early overnight period...with
ADF...PBF and LLQ having the best opportunity for seeing
convection. Some MVFR or lower flight conditions will be
possible...especially under the most intense activity. Chance for
precip decrease considerably further north...with HRO and BPK
maybe seeing some morning MVFR fog due to light winds around
sunrise.
&&
.PREV DISCUSSION...(ISSUED 251 PM CDT Wed Jun 19 2019)
Short Term...Tonight thru Friday...
Short term models are continuing to indicate convective initiation
later this evening across NE TX/SE OK, with convection moving into
AR around 00Z or shortly thereafter. NAM and RAP forecast soundings
across southwest AR show CAPE values in excess of 4000 j/kg.
Convection should spread and expand this evening across much of
southern AR. With the upper trof, extensive instability, and an
approaching surface boundary - storms should become quite strong to
possibly severe, especially during the evening hours. Damaging winds
are probably the most likely threat, although in the evening hours I
would also suspect that large hail may also occur.
After this system clears out, an upper ridge is going to start
building across the area. By Friday, temperatures across the area
should reach the lower 90`s across the north, with mid 90`s
elsewhere. With dewpoint values anticipated to be in the mid 70`s,
this will bring heat index values close to heat advisory
criteria...which is 105 degrees.
Long Term...Saturday thru Wednesday...
Not many changes to the going forecast. The period begins with a
well established H250/H500 ridge planted across the central CONUS.
On Saturday, the upper ridge will shift eastward a bit allowing for
southwesterly flow to become re-established in the mid/low levels
across the Southern Plains. At the surface, southwesterly winds will
have already returned as low pressure develops over the Rockies.
On Sunday, an upper level short wave will move over the Rockies
further amplifying the flow between the tough and ridge over the
Great Lakes region. This short wave trough will pivot around a much
larger low over Canada. As this happens, an associated surface cold
front will approach the state from the north and west. Low level
southwesterly winds will increase in response to tightening pressure
gradient between the aforementioned surface low over the Plains and
surface high pressure over FL. Warm and moist air will continue to
advect into the region destabilizing the atmosphere heading into
Monday. High temperatures over the weekend will top out in the upper
80s to mid 90s. Dew point temperatures will be in the upper 60s to
lower 70s resulting in heat indices between 100 and 105 on Saturday
and Sunday.
Monday, showers and thunderstorms are expected to develop along and
ahead of the front where the best lift and instability will be
found. Some strong to severe thunderstorms will be possible during
the afternoon and evening time frame. Temperatures will reflect
abundant cloud cover with highs only in the lower 80s to around 90
degrees. The front will not stay long because it will begin to lift
northward as a warm front.
By Tuesday, the upper pattern becomes more zonal as the trough
slides north and east. Upper level ridging will one again build into
the region to end the period. A stalled surface boundary will become
the primary focus for afternoon showers and thunderstorms each
afternoon.
&&
.LZK Watches/Warnings/Advisories...NONE.
&&
$$
Aviation...62
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1058 PM CDT Wed Jun 19 2019
.UPDATE...
Issued at 1058 PM CDT Wed Jun 19 2019
Updated for 06z Aviation discussion.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 214 PM CDT Wed Jun 19 2019
The main change to the forecast for the short term period through
Thursday night was a to reduce the chance of precipitation across
mainly the eastern half of MN and western WI, as well as slow
down the arrival of precipitation across western MN overnight into
tomorrow morning.
Latest model guidance and addition of hi-res guidance covering the
period are in good agreement in drier/lower chance of
precipitation tomorrow across eastern MN and western WI. As of this
afternoon, the main upper level low of concern is across British
Columbia and Alberta. This low will strengthen this afternoon and
tonight, and slowly sag south toward Idaho and western Montana.
Shortwave energy will be released ahead of the main upper low
tonight, making it`s way east into the Dakotas by early Thursday
morning. This is the point where the forecast changed from the
previous. The guidance now lifts the upper jet streak quickly north
during the day taking the upper level forcing north as well. In
addition, the PV advection with the shortwave now looks to enter
western MN tomorrow morning, but lift northeast as it remains
wrapped in with the mean cyclonic flow of the parent upper low,
still positioned over extreme western Montana by 18Z tomorrow.
Lastly, theta-e advection and frontogenesis in the 700-600mb layer
really diminish quickly from western MN to the east as warm air
advection becomes nearly non-existent across the forecast area during
the day.
This leads to similar pops in western MN (60-80 percent) tomorrow
morning, but as the forcing lifts north toward mid day, expect
nothing more than decaying showers (possibly very isolated thunder)
to reach eastern MN and western WI. Hence, pops were dropped to
around 20 percent along the I-35 corridor and lower to the east.
Thunder chances are rather low giving the weakening forcing through
the day. QPF was lowered as well, with less than 0.1" expected for
eastern MN and western WI. The best chance of precip will be in the
Alexandria area, where a quarter to half an inch is possible.
.LONG TERM...(Friday through Wednesday)
Issued at 214 PM CDT Wed Jun 19 2019
The longer term continues to look warmer and more unsettled
overall. We`ll see short wave ridging develop the area for the end
of this week into the weekend before the trough currently dropping
into the northwest works its way east and across our area. There
remains some disagreement in the details of how this occurs,
particularly with respect to frontal features and timing, which
will play into how much of a severe weather threat we`ll see from
Friday into Saturday. After that, we will see troughing develop
along the west coast next week, leading to more pronounced and
what should be more persistent ridging over the center of the
country by midweek. We should see SHRA/TSRA develop to our west
Friday then work through the area late Friday into early Saturday.
We may then get additional development Saturday afternoon
depending on where the surface low and associated fronts wind up.
The guidance is not in especially good agreement on those details
at this point. Some of the guidance keeps the southwest to
northeast oriented baroclinic zone over the area through Sunday,
allowing for surface waves to impact the area both Saturday and
Sunday. Given the uncertainty and generally favorable pattern for
active weather, will keep PoPs going through the weekend. We don`t
have wholesale agreement in drying things out until later Monday
into Tuesday, so don`t really knock down chances for precipitation
until then, when we finally look to get into some northwest flow
for a period of time. Chances for SHRA/TSRA from then into
Wednesday look to be more spotty as ridging works to establish
itself and instability increases across the region.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1058 PM CDT Wed Jun 19 2019
Showers associated with an upper wave near Fargo will slowly
dissipate near AXN over the first couple of hours of the TAFs.
Wave coming out of WY/MT now will work across the Dakotas
overnight, with a N-S band of showers approaching western MN Thu
morning. Still lower confidence in how this band will evolve, as
it will be running out of forcing and instability as it works
across MN. Lots of spread in the CAMS tonight with how widespread
this activity will be and how far east it will work, but we are
seeing enough guidance driving showers into eastern MN in the
afternoon ahead of a weakening shortwave to include a VCSH at all
MN terminals. Only field that looks to have an MVFR threat this
period is AXN, but the LAV/LAMP are outliers with how low they
take cigs out there, so kept them VFR for now until more guidance
shows that threat as well.
KMSP...The HRRR along with several of the 00z hi-res models push
scattered showers into the metro Thursday afternoon, so decided to
add a vcsh to cover that threat. 19z to 00z looks to be the precip
window.
/OUTLOOK FOR KMSP/
Fri...VFR. SHRA/TSRA/MVFR likely late. Wind SE 10G20 kts.
Sat...MVFR likely. Chc SHRA/TSRA. Wind SE 5-10 kts.
Sun...VFR. Chc MVFR/SHRA/TSRA. Wind SW 5 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
&&
$$
SHORT TERM...SPD
LONG TERM...
AVIATION...MPG
Area Forecast Discussion
National Weather Service Norman OK
1034 PM CDT Wed Jun 19 2019
.DISCUSSION...
&&
.AVIATION...
For the 06z TAFs:
VFR conditions are expected to prevail. Winds may be variable
initially but should be more consistently south-southeasterly from
morning onward. Wind speeds could peak during the afternoon around
12-15 knots.
&&
.PREV DISCUSSION... /issued 638 PM CDT Wed Jun 19 2019/
DISCUSSION...
00Z TAFs.
AVIATION...
Scattered thunderstorms will affect portions of northern Oklahoma.
The current storm movement will take the storms between KWWR and
KPNC, so have not included a TEMPO group at either site, but the
possiblitity of affecting one or both of them is certainly there.
There will also be the possibility of gusty outflow winds from
these storms affecting these two airports even if the storms do
not reach the vicinity. Otherwise, VFR conditions are expected
with generally light winds overnight increasing from the south
Thursday morning.
PREV DISCUSSION... /issued 604 PM CDT Wed Jun 19 2019/
.Update...
DISCUSSION...
Quick update to increase probabilities of precip in north-central
Oklahoma. Storms with sustained mid-level rotation and hail up to
3 inches and diameter in Kansas will be in a thermodynamic
environment favorable for sustenance for at least a few more
hours. Effective shear is marginal but supportive. These appear
to be strongly diurnally driven with comparatively limited
moisture further north and fairly high bases. Nevertheless, RAP
soundings upstream suggest that they should continue through at
least mid- evening with an attendant hail/wind threat. 2m theta-e
slowly decreases late in the evening and this should result in
decreased intensity. Some evolution toward more of a wind threat
with time is possible as cold pool matures/grows.
Further south, confidence in storm initiation in the Tornado Watch
isn`t particularly high immediately north and west of ongoing
impressive supercells south of the Red River. Visible satellite
indicates storm-scale subsidence on the western flank having a
deleterious affect to cumulus field from between Gainesville and
Sherman northward into Marshall and portions of Bryan Counties.
One anticyclonic meso near Bonham has weakened as it moves toward
far southeast Bryan County. Persistent attempts at convection have
been noted near the Red River in Love county on visible satellite
(i.e., persistent attached small anvils/glaciation). Further west
into Clay County, cumulus is still present but even orphan anvils
have decreased over the last 30 minutes or so. Further north
toward Atoka and Tishomingo, a more stable environment is evident
by more of a billow look to cu structure in satellite, thus the
threat drops of markedly. This is coincident with the north edge
of more significant low level moisture/instability gradient. Thus,
probabilities were decreased across this area. We`ll continue to
monitor trends and consider early cancellation of the Tornado
Watch.
BRB
PREV DISCUSSION... /issued 400 PM CDT Wed Jun 19 2019/
DISCUSSION...
A boundary is observed on visible satellite in southern Oklahoma
and western north Texas where cumulus developing is occuring south
of the boundary. This boundary will act as a catalyst for
possible severe weather later this afternoon and evening. Forecast
soundings show ample CAPE (>3000J /kg) and sufficient deep shear
(>30kt SFC-6km) could lead to a decent chance for developing
severe storms with large hail and damaging winds. Severe potential
will diminish as this boundary shifts southeast overnight.
A low amplitude upper level ridge will set into place Thursday into
Friday which is expected to clear out the skies. Some westerly
surface flow and downsloping are expected to further increase the
surface heating Thursday and Friday prior to a switch to a southerly
wind and enhanced moisture return. While dry conditions and no
precipitation is anticipated, the increased heating and moisture
return may destabilize the surface enough that some convection and
isolated thunderstorms could happen in far western Oklahoma and
western north Texas. Confidence is low in precipitation chances
Thursday evening, while precip chances were included for Friday
evening.
On Friday, an upper level ridge and high pressure cyclone sets up
yet again over the Gulf of Mexico, enhancing the moisture transport
into the region. An approaching upper level low pressure cyclone
will produce numerous shortwaves and upper level support for
precipitation on Saturday onward. A cold front is anticipated to
enhance precipitation chances over the weekend, however the timing
and location of the precipitation is uncertain as of this forecast.
Consistent moisture advection into the region throughout next week
will present the chance for additional precipitation.
Zwink
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 85 66 93 73 / 10 20 0 10
Hobart OK 88 66 97 74 / 10 20 0 0
Wichita Falls TX 93 69 100 77 / 10 10 0 0
Gage OK 84 63 93 68 / 30 30 10 0
Ponca City OK 81 64 91 71 / 20 20 0 10
Durant OK 90 68 94 76 / 30 30 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&
$$
26/12/12
Area Forecast Discussion
National Weather Service Paducah KY
932 PM CDT Wed Jun 19 2019
.UPDATE...
Issued at 932 PM CDT Wed Jun 19 2019
Plan to maintain scattered shower and thunderstorm chances through
the evening hours.
The RAP was showing a almost triangular area of 1500-3500 CAPE
with 35-40 knot shear in 40-50 mile radius around the impressive
thunderstorm that developed west of KPOF earlier this evening.
Until recently, have not seen alot of splitting with these storms,
but the one near KCGI has been a left-mover.
Most of the thunderstorms have been developing along the trailing
edge of a deep layer moisture gradient per differential water
vapor imagery. KPAH and KVWX radar showing some mid-level veering
(mid level shortwave) rotating above capped flow below. However,
flow continues to veer this evening through the layer, so still
worth monitoring.
Northern area of convection (over Jefferson and Wayne Co IL)
appears to have run into lesser favorable environment to maintain
thunderstorms, so not much concern there at this time.
At this point, not sure how much more fuel these thunderstorms can
access before running into contaminated/mixed air from earlier
convection today. RAP is suggesting some lowering of CAPE (down to
1500 j/kg2 and marginal mid-level lapse rates further east into
southern Illinois and the northern section of the Purchase area of
west KY. However, may see some maintenance of the stronger storms
into southwest IL and along the KY/TN border through at least
230z-330z.
&&
.SHORT TERM...(Tonight through Friday night)
Issued at 300 PM CDT Wed Jun 19 2019
Ongoing scattered to numerous thunderstorms will likely continue
into the late afternoon and early evening. SBCAPES have been
running upward of 1500-2500 J/KG with DCAPES up close to 1000 J/KG
over portions of southeast MO/wrn KY. 0-3 KM Bulk Shear has been
marginal, generally 30-35 kts, but effective bulk shear has been
running closer to 40 kts along the MS River, where some storms
have reached severe limits this afternoon. In addition, emanating
outflow boundaries from ongoing storms will likely serve to kick
off additional convection. It should be noted that these storms
also have a history of producing a half inch of rainfall in about
15 minutes. Will continue with a flash flood watch for those
portions of southeast IL/sw IN that have received the most
rainfall in the past several days. Storms are expected to become
a bit weaker and less widespread after dark tonight as we lose a
good deal of low lvl instability. However, cannot rule out
additional heavy downpours and some gusty winds.
A weak area of sfc high pressure will move east into the region
behind this system on Thursday, leading to an end to most rain
chances and slightly cooler and less humid conditions. However,
the heat and humidity will be cranked back up as we finish the
work week. In fact, would not be surprised to see heat indices at
some locations top 100 degrees Friday afternoon if we manage
enough sunshine. A few warm advection showers and thunderstorms
cannot be ruled out, esp during the heat of the
afternoon/evening. However, thinking now the best overall forcing
will remain off to our nw and north. Could be more of a pulsey
situation where storms manage to form. In fact, ridging aloft
could also serve to somewhat temper the convection.
.LONG TERM...(Saturday through Wednesday)
Issued at 300 PM CDT Wed Jun 19 2019
Models are in fair agreement at the start of the extended. The ECMWF
may be a little to fast with the system Saturday. The Canadian may
be a little slow. So will lean toward a compromise which would be
ECMWF.
We start off Saturday with an upper level high center over the Gulf
with a the apex of the ridge rising into canada. However there will
be some weak perturbations caught in the flow in the ridge itself.
This will keep a chance of rain in the forecast or storm. The main
impact for Saturday be the heat. We are looking for high
temperatures around or in the 90s with dew points in the 70s. This
should produce heat index values between 100 and 105. These
perturbations will continue to eject out of long wave trough over
the central rockies. This trough will make its way eastward across
the plains. This will begin to break down the ridge a keep rain
chances into next week. Rain chances will continue into the middle
of next week although chances and coverage are much lower. Also
temperatures and dew points will moderate slightly brining a little
less oppressive conditions to the region.
&&
.AVIATION...
Issued at 605 PM CDT Wed Jun 19 2019
With the 00z Thursday WFO PAH TAF issuance, attempted to depict
the departure from or the passage through of convection over KOWB
and KMVN early in the period. Adjusted ceilings into the MVFR
category between 09z and 15z to reflect the approach of the weak
surface frontal wave near the TAF locations.
Otherwise VFR conditions with scattered MVFR cloud bases will be
the rule through most of the forecast period.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...Flash Flood Watch until 6 AM CDT Thursday for ILZ075>078-082-083.
MO...None.
IN...Flash Flood Watch until 6 AM CDT Thursday for INZ081-082-085>088.
KY...None.
&&
$$
UPDATE...Smith
SHORT TERM...GM
LONG TERM...KH
AVIATION...Smith
AREA FORECAST DISCUSSION
National Weather Service Charleston WV
812 PM EDT Wed Jun 19 2019
.SYNOPSIS...
One upper disturbance crosses tonight. Another, along with a
surface cold front cross Thursday. Warm sector into the
weekend. Next cold front early next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 810 PM Wednesday...
The forecast remains on track, however made some minor
adjustments to match current observations and trends as well as
gave QPF a fresher look with the help of updated model
guidance.
As of 600 PM Wednesday...
The forecast still remains on track as things currently calm
down a bit, however some convection is still on the table for
this evening into the overnight. No significant changes were
needed to the forcast at this time and with all the heavy
downpours and rain accumulations that have been observed for the
day, the flash flood watch still remains in effect until
Thursday evening.
As of 200 PM Wednesday...
We are still stuck in the same pattern we have been for most of
the week, with southerly flow pumping moisture into the forecast
area, and ripples in the 500mb flow driving areas of showers and
storms. We did get some sunshine this afternoon, so have a bit
more cellular convection ongoing due to 500-1000 J/kg MLCAPE
added by the solar heating. With limited shear, not expecting
much organization to the storms, but any taller cells could be
capable of marginally severe wind gusts, which is reflected by
the SPC Day 1 outlook.
Overnight, expect showers and storms to lessen in coverage
initially, but as another 500mb shortwave trough crosses think
coverage will pick up again and have gone with an area of likely
POPs crossing from west to east after midnight.
A surface low will cross northern Ohio on Thursday, with a cold
front crossing the forecast area. This, combined with 500mb
ripples working through the mean trough and lingering outflow
boundaries from earlier activity will lead to showers and
thunderstorms on Thursday. Tried to put some timing info for the
best chance of storms using the WRFNMM... but really a
shower/storm could be around any time with abundant moisture and
multiple modes of synoptic and mesoscale forcing moving
through. The NAM is not really impressed with instability for
Thursday, while the RAP shows up to 2000 J/kg of MLCAPE.
Instability will be highly dependent on how much sun we get
during the late morning and early afternoon. Right now, think we
will have pretty widespread cloud cover, limiting the strength
of storms, but confidence is not great. We will see better bulk
shear moving through during the day, so if we do get some
sunshine, the RAP could be on to something, with stronger storms
possible during the afternoon with strong winds the main concern.
SPC marginal risk across the eastern half of the forecast area
also reflects this possibility, with the better chance of
severe weather to the east where instability should be better.
Flash flood watch remains in effect into Thursday evening.
Precipitable water values will remain in the 1.5-2 inch range
along and ahead of the cold front, so any stronger shower or
storm could produce heavy rainfall and localized flooding.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 230 PM Wednesday...
High pressure builds behind the front Thursday night to provide
dry and weak flow conditions through Saturday morning. Then, a
warm front develops and lifts slowly north through Sunday.
Scattered showers or storms are possible while the area remains
in the warm sector of the incoming weather system.
Models suggest an H500 disturbance digs southeast across or just
south of our Tri-state area near HTS. This disturbance could
bring some precipitation to portions of southeast OH, northeast
KY and southern WV late Friday night into Saturday.
There will be a gradual warm up each day with temperatures
reaching the low 80s lowlands of WV, KY and southeast OH,
ranging into the mid 60s highest peaks northeast mountains.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 230 PM Wednesday...
The aforementioned warm front will slowly lift north Saturday
night, positioned over our northern third of the area by Sunday
morning. While on the warm sector, showers and storms will be
possible during this time period.
Some model differences are noted beyond Sunday on other upper
level disturbances affecting the area Tuesday on.
It will continue warm with highs reaching the mid to upper 80s
lowlands, ranging into the lower 70s northeast mountains.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
As of 725 PM Wednesday...
Although the storms have settled down there will be an opportunity
for them to make an appearance throughout the night while a
trough crosses the area and the cold front to the west moves
closer. Mainly VFR conditions start off with a chance of a pop-
up storm in the vicinity until late morning. Because of issues
with timing thunderstorms decided to insert vicinity into TAFs
at prime times of possible activity. Visibility may be
restricted in a heavier shower due to rain induced fog,
otherwise unrestricted VIS expected through the overnight into
the morning. Winds will be strong enough along with enough cloud
coverage to deter fog. South-southwest flow changes over to
westerly by tomorrow afternoon with frontal passage and increase
from 5KT to 10-15KT sustained. Look for gusts up to 25KT in the
afternoon at any terminal along with possible storms.
As the cold front crosses in the late afternoon expect more
thunderstorm activity for the rest of the day. MVFR may turn to
IFR in thunderstorms and heavier rain showers.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z FRIDAY...
FORECAST CONFIDENCE: Low to medium.
ALTERNATE SCENARIOS: Timing of restrictions may vary, and
amendments may be needed for showers and thunderstorms.
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 THU 06/20/19
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 H H H H H H
HTS CONSISTENCY H H H H H H L H H H H H
BKW CONSISTENCY H H H H H H H H L H H H
EKN CONSISTENCY H H H H H M M M M L M M
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H M L L
AFTER 00Z FRIDAY...
Brief IFR conditions likely at times with showers and
thunderstorms into Thursday evening. IFR in fog/stratus
possible Thursday night into Friday. Brief IFR possible in
showers and storms this weekend.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Flash Flood Watch through Thursday evening for WVZ005>011-
013>020-024>034-039-040-515-516.
OH...Flash Flood Watch through Thursday evening for OHZ066-067-075-
076-083>087.
KY...Flash Flood Watch through Thursday evening for KYZ101>103-105.
VA...Flash Flood Watch through Thursday evening for VAZ003-004.
&&
$$
SYNOPSIS...26/MZ/JZ
NEAR TERM...MZ/JZ
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...JZ