Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/01/19
Area Forecast Discussion
National Weather Service Bismarck ND
1040 PM CDT Wed Jul 31 2019
.UPDATE...
Issued at 1040 PM CDT Wed Jul 31 2019
The remainder of the severe thunderstorm watch has been allowed to
expire as scheduled.
UPDATE Issued at 947 PM CDT Wed Jul 31 2019
As expected, storms are diurnal in nature and have been
downtrending the past hour or so. Will allow the watch to continue
north central through the next hour where some robust convection
continues. Otherwise the majority of the watch has been expired.
UPDATE
Issued at 550 PM CDT Wed Jul 31 2019
Severe thunderstorm watch number 548 has been issued for most of
western and north central North Dakota this evening. Storms have
initiated across the west and have gradually increased in
intensity as the capping inversion erodes. Steep lapse rates and
decent shear around 35 kts will create a favorable environment for
large hail. Winds will become a threat as storms collapse. Storm
motion has been slow, so will also be looking at heavy rain
producing a flash flood threat. Convection is expected to be
diurnal with lack of good mid level forcing, so the main window
for severe will be this evening. Little to nothing is expected
over my southeastern areas with weaker lapse rates and stronger
inhibition.
&&
.SHORT TERM...(This afternoon through Thursday)
Issued at 234 PM CDT Wed Jul 31 2019
A slight risk for isolated strong to severe thunderstorms
highlights the short term forecast.
Currently, a large area of low pressure is centered across eastern
Montana, southern Saskatchewan, and far western North Dakota,
with a frontal boundary oriented northeast to southwest. As this
boundary slowly pushes east, isolated to scattered showers and
thunderstorms are expected to form along this line in a moderately
unstable environment in western North Dakota. Temperatures along
the MT/ND border are in the mid 80s, expected to rise to the low
90s, while low cloud cover across parts of central North Dakota
has really hindered daytime heating. Southerly winds ahead of the
front have been advecting in moisture, with surface dew points in
the mid to upper 60s. Main thinking right now is that this is a
conditional severe threat, with RAP sounding analysis hinting that
convective inhibition will be quite strong across central North
Dakota, but somewhat weaker across the west especially if surface
temps continue to rise. MUCAPE values range from 1500-2500 J/kg
and model guidance shows steep low level lapse rates, but deep
layer shear is only around 25-30 knots. The shear does look to be
almost perpendicular to the boundary, so expecting a mostly
discrete storm mode, which will help enhance the isolated
wind/hail threat. HREF updraft helicity tracks are short and
scattered so again thinking this will be an isolated threat that
won`t extend much into central North Dakota. Chance of storms dies
off rather quickly tonight as this event is mainly diurnally-
driven, with low temperatures tonight in the upper 50s north to
mid 60s south.
On Thursday, the upper-level ridge becomes centered over the
Northern Plains with the same frontal boundary from today becoming
oriented much more west to east through the center of North
Dakota. A shortwave moving through the mean flow will help heights
be more neutral to slightly falling, compared to height rises
today, which will help with more overall ascent. The chance for
scattered showers and thunderstorms returns in the afternoon with
another moderately unstable environment developing and high
temperatures in the mid to upper 80s.
.LONG TERM...(Thursday night through Wednesday)
Issued at 234 PM CDT Wed Jul 31 2019
Almost daily thunderstorm chances before a slight cool down next
week highlights the extended forecast.
As upper level ridging continues through the weekend, North Dakota
will remain in a pretty typical summer weather pattern with warm
temperatures and almost daily chances for showers and
thunderstorms. Thursday and Friday night both have widespread
chances for thunderstorms across all of western and central North
Dakota as shortwaves move through the ridge and instability
remains high, but still a large amount of uncertainty in storm
severity and location. Model guidance is hinting at a cold front
moving south through the region for the start of next week, with
forecast high temperatures in the low 80s for the beginning of the
work week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 550 PM CDT Wed Jul 31 2019
Scattered showers and thunderstorms are possible mainly in
western and north central North Dakota this evening but low
confidence in specific location so did not include any TEMPOS at
this time. Did mention VCTS for KDIK with storms just to the west-
southwest of the Dickinson airport. Winds are primarily around 10
knots from the south-southeast with a cold front approaching
western North Dakota. Low cloud deck expected to move into
southern North Dakota early tomorrow morning, possibly lowering
ceilings to MVFR at KDIK/KBIS/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...MJ
LONG TERM...MJ
AVIATION...NH
Area Forecast Discussion
National Weather Service Brownsville TX
631 PM CDT Wed Jul 31 2019
...00z Aviation Update...
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...A very quiet TAF period ahead with VFR conditions
expected to prevail. Light southeasterly winds (10kts or less)
expected. Only high clouds from remnant convection upstream, but
again it`s difficult to find much to talk about through this
cycle. Safe Travels!
&&
.PREV DISCUSSION... /issued 247 PM CDT Wed Jul 31 2019/
SHORT TERM (Now through Thursday Night): It`s been a hot, but
relatively quite day, weather-wise, across the Rio Grande Valley and
Deep South Texas. KBRO doppler radar shows a dissipating cluster of
thunderstorms just north and east of the BRO offshore coastal
waters, moving southwest. A slightly drier and more stable airmass
in place over the RGV will likely continue eroding this activity.
This is confirmed by the latest hi-res HRRR model, which shows the
storms dissipating before reaching any land areas. Will continue to
monitor this activity, just in case. The seabreeze has been
uneventful thus far, currently draped across the immediate coastline
of all three coastal counties. Not expecting much precipitation
development along the seabreeze this afternoon, but cannot
completely rule out an isolated shower/thunderstorm or two before
sunset.
A stout 595dam ridge current centered over the TX/OK Panhandles will
remain stagnant over that same area over the next couple of days.
Temperatures are forecast to trend closer seasonal average tonight
through Thursday night as slightly drier air and cooler 850mb
temperatures. Highs will be in the mid-upper 90s east of I69C and
near 100 to 103 degrees west of I69C; lows will generally be in the
mid-upper 70s. Rain chances will be minimal through Thursday night,
with the best chances occurring off the coast. Kept in 20% pops east
of I69C through the morning and day on Thursday, but only expect
isolated convection with limited moisture available.
As far as fire weather concerns: Relative humidity values will
continue to be in the 20 percent range for western portions of Deep
South Texas on Thursday afternoon. However, wind speeds are expected
to be below criteria for fire weather concerns.
LONG TERM (Friday through Wednesday): The persistent mid level
Monsoon ridge over the Southwestern States into the South Central
Plains will continue into the long term and will shift slowly west
through the weekend as a broad 500 mb trough digs into the Gulf
of Mexico. The combination of the persistent mid level weakness
over the Gulf and ample low level tropical moisture should support
isolated to scattered convection near the lower Texas coast and
over the Gulf Waters, if not weak daily sea breezes. The 500 mb
ridge will build into North Central Mexico and West Texas by early
next week. Temperatures will trend toward above normal through
the forecast, with afternoon heat index values of 103 to 108
through the weekend, and a skosh higher, 105 to 110 degrees going
into the next work week. The global models, though not in
unequivocal agreement, are in fair agreement for this neck of the
woods with no apparent major weather distractors. Will therefore
lean toward a model consensus.
MARINE...(Now through Thursday Night): No major changes made to
forecast from this morning. Marine conditions will be generally
favorable for the short term period featuring light to moderate
southeasterly winds and low seas. Isolated to scattered showers
along with thunderstorms may be possible at times, especially
offshore from 20 to 60 nm out. Heavier showers or thunderstorms may
result in locally gusty winds and isolated agitated seas.
Friday through Monday Night: Light to moderate southeast winds and
low to moderate seas will prevail through the forecast. There will
be isolated showers and thunderstorms. Mid level ridging centered
roughly over the southwest United States will counterbalance broad
mid level troughing over the eastern sections of the country, which
will extend south to over the north central Gulf. The combination of
moisture moving up from the south on the large scale southeast flow
will be modestly destabilized by the weakness aloft, supporting
marine convection.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
This product is also available on the web at:
HTTP://WEATHER.GOV/RGV
Aviation Update...Frye-55
Area Forecast Discussion
National Weather Service Dodge City KS
1055 PM CDT Wed Jul 31 2019
...Updated Aviation...
.SHORT TERM...(This evening through Thursday)
Issued at 202 PM CDT Wed Jul 31 2019
Very weak cyclogenesis will be developing are area of enhanced
surface convergence across southwest and central Kansas late this
afternoon through the overnight. The CAMs have been showing for
many runs now isolated to scattered convection within this low
pressure area as early as 21 UTC, initiating in far southwest
Kansas and expanding into the I-70 corridor around Hays and
Wakeeney by around 7 or 8 pm. Deep layer shear is generally weak
as the upper ridge has dominated the area for days, however steep
mid level lapse rates will promote deep updrafts and a threat for
perhaps a marginally severe wind gust and locally heavy rain and
lightning continuing through the late evening hours far beyond
sunset. Beyond the convective threat through the late evening, the
lows tonight should be very warm in the mid 70s across the
central Kansas counties, and not as warm out in the higher
elevation counties near the Colorado line.
.LONG TERM...(Thursday night through Wednesday)
Issued at 221 PM CDT Wed Jul 31 2019
A cold front on Friday may be the focus for a few thunderstorms,
again weakly sheared, so severe threat should be minimal. Light
easterly upslope will develop after the frontal passage, with a
number of days to follow with continued persistent upper ridging
across the southern Rockies and central/southern High Plains.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1055 PM CDT Wed Jul 31 2019
VFR will continue to prevail through this TAF cycle. Mid level
convective debris clouds will gradually dissipate overnight, with
surface winds light and variable in direction. A weak wind shift
or frontal boundary will sag southward through SW KS daylight
Thursday, keeping surface winds highly variable in direction at
GCK/DDC (but generally less than 10 kts). Light NE winds will
prevail at HYS Thursday north of the boundary, while SW winds
prevail with modest gusts at LBL south of the boundary. Scattered
to broken mid layer cloud decks are expected. Carried no
convection in this set of TAFs and kept the airports dry.
Thunderstorms in NE Colorado 00-03z Fri may organize into a
complex and approach the airports 03-09z Fri, as shown by the
latest HRRR iterations. Confidence is low on coverage this far
out. Models do show a reinforcing cold front surge with enhanced
N/NE winds of 15-25 kts near the end of this TAF cycle (near 06z
Fri). Consensus of short term models suggest that post-frontal IFR
stratus cigs are possible Friday morning.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 74 102 73 94 / 20 0 10 0
GCK 70 101 69 92 / 40 0 10 10
EHA 71 100 69 93 / 10 0 10 20
LBL 71 101 72 93 / 10 0 10 10
HYS 72 96 71 89 / 40 0 20 10
P28 74 103 75 97 / 10 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Turner
Area Forecast Discussion
National Weather Service Grand Forks ND
1000 PM CDT Wed Jul 31 2019
.UPDATE...
Issued at 1000 PM CDT Wed Jul 31 2019
Thunderstorms moving down from Canada have increased in strength a
bit as they cross the border into Cavalier county. With ML CAPE
values around 3000 J/kg and effective bulk shear of 30-35 kts
think that strength will be maintained for a bit longer until we
start to lose residual heat from daylight. Bumped up POPs a bit
across our far north for the next few hours. CAMs have the cells
slowly sinking south across the Devils Lake Basin and northern
RRV, with the HRRR most bullish on convection holding together
past 06Z. Other CAMs and even other runs of the HRRR are not as
strong. Have POPs slowly tapering to isolated after the 06-08Z
time frame, and will adjust if needed.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 335 PM CDT Wed Jul 31 2019
The main challenge for this time frame is thunder chances.
Currently not a lot is happening. There was a lot of cloud cover
west of the FA this morning, which limited the heating somewhat.
However it is fairly clear now with temperatures back into the low
80s and dew points in the mid 60s to low 70s. This is giving
surface based CAPE values of 3000+ J/kg over western and central
ND with just a little CIN left. Effective shear is around 30
knots and precipitable water values at about 1.2 to 1.3 inches.
Surface boundaries are a little diffuse. However high resolution
models do show storms developing over western ND in the late
afternoon and early evening. Some of these storms may hold
together as they reach the Devils Lake region by mid to late
evening. However, the sun will be setting by then and the low
level jet and 850mb warm advection is not that impressive.
Therefore think these storms will weaken as they approach the
Devils Lake region. Think most activity will diminish by late
evening, but some of the high resolution models show a shower or
weak storm lingering into the overnight hours up along the
Canadian border.
Thunder possibilities into Thursday are a bigger challenge. A
remnant surface boundary may be draped across the northern half of
the FA on Thursday. Some models show additional shower and weaker
storm activity lingering in the morning, but there are better
chances for a few strong to severe storms again by afternoon. The
northern half of the FA remains in a marginal risk, so the
potential is there.
.LONG TERM...(Thursday night through Wednesday)
Issued at 335 PM CDT Wed Jul 31 2019
Lots of uncertainty by Thursday night, so pretty much left low
precipitation chances across the entire FA. Should have a better
idea on how much activity may linger Thursday night with later
forecasts.
Thunderstorms will be possible for late day and eve Fri, but weak
forcing for ascent will allow for only isolated storms. Continued
weak deep layer shear will also limit the severe potential. What we
will have at the surface should be a weak synoptic boundary
somewhere over the northern forecast area below mainly
northwest flow aloft.
This northwest flow will always make it difficult to pinpoint
spatial and temporal extent of storms, but there is indication of a
somewhat more substantial surface boundary and associated upper wave
for later Sun. Another opportunity presents about 24 to 36 hours
later, then a more zonal upper pattern could make for a more settled
dry period Tue into the middle of next week.
Temps during the period will rise to above average levels, mainly
in the mid to upper 80s Fri through Mon, trending down a bit
thereafter. Lows will be in the balmy 60s much of the time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 614 PM CDT Wed Jul 31 2019
VFR conditions throughout the period. The high resolution models
have some convection entering the KDVL area later in the evening,
which makes sense given cells starting to form in southern
Manitoba. Have VCTS at KDVL but will keep it out of the TAF sites
further east. Winds gusting above 20 kts at some sites will
subside after sunset, with winds from the south at less than 10
kts for the rest of the period.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...JR
SHORT TERM...Godon
LONG TERM...WJB/Godon
AVIATION...JR
Area Forecast Discussion
National Weather Service Goodland KS
542 PM MDT Wed Jul 31 2019
.UPDATE...
Issued at 542 PM MDT Wed Jul 31 2019
Updated forecast for this evening and tomorrow to adjust
thunderstorm chances. High resolution guidance suggest storms will
likely remain in the southern portion of the forecast area
although attention will need to be paid along the I-70 corridor
as storms have developed in northeast Colorado and additional
storms may develop. For tomorrow, high resolution guidance
indicating a larger complex of storms forming in northeast
Colorado, spreading through the region in the evening hours (6 pm
to Midnight mountain time). Some storms may be severe with
damaging winds as the main threat. Would not rule out some large
hail, some very large hail due to the expected instability.
Tomorrow`s situation definitely bears watching.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 400 PM MDT Wed Jul 31 2019
Overview: Modest W-NW flow aloft will persist over the Tri-State
area -- on the northeast periphery of an upper level ridge
centered over New Mexico.
Today-Tonight: Weak low-level convergence invof a broad surface
low (centered near Lamar CO) -- and an associated thermal/
moisture boundary extending northeast from Lamar-Tribune-Gove
City-Hill City -- will serve as a focus for convective development
this afternoon.
Per 21Z SPC mesoanalysis, MLCAPE values across the Tri-State area
ranged from 500 J/kg (eastern CO) to 1000-1500 J/kg (western KS),
though a significant amount of convective inhibition persists
north of the TMB (north of I-70) where 100-200 J/kg of CINH
persists near the KS/NE border. Simulated reflectivity forecasts
via the 18Z NAM NEST and past several runs of the HRRR are (1)
doing a good job in depicting ongoing convection invof Hwy 50 this
afternoon and (2) are consistent with the latest mesoscale/
thermodynamic environment analyses. With this in mind, expect
isolated unorganized thunderstorms to largely be confined south of
I-70 this aft/eve -- primarily in Kit Carson/Cheyenne counties in
CO and Greeley/Wichita/Gove/Logan counties in KS - with activity
gradually waning/dissipating after sunset.
Thu-Thu night: With little change in the synoptic pattern, the
convective forecast on Thursday may largely be a function of
upstream convection. More specifically, guidance suggests that
mesoscale features emanating from deep convection over Wyoming
tonight/tomorrow morning may aid/enhance diurnal development along
the CO Front Range tomorrow afternoon -- and that the ensuing
activity will propagate SSE into eastern CO between 00-06Z. Though
an MCV may well keep convection going after sunset, activity is
still likely to wane/dissipate by midnight -- possibly without
crossing the CO/KS border.
.LONG TERM...(Friday through Wednesday)
Issued at 125 PM MDT Wed Jul 31 2019
At the start of the period, an upper ridge extends across the
Rockies, with high pressure centered over the Four Corners. The
tri- state region is under northwest flow on the eastern side of
the ridge as a result.
A disturbance continues on its way around the periphery of the
ridge on Friday, generating chances for showers and thunderstorms
mainly in the afternoon and evening hours across the area. The
pattern remains similar through the weekend, with the ridge
staying west of the High Plains. No major weather disturbances are
anticipated on Saturday or Sunday, leading to a dry forecast at
this time. However, will need to monitor the potential for a
couple of weak waves triggering storm development.
Daily precipitation chances return early next week, with a
possibility of thunderstorms each afternoon and evening Monday
through Wednesday. Current guidance suggests the ridge is pushed
somewhat southward with a series of shortwaves rotating through
the flow. Models differ during this timeframe, making it difficult
to have confidence or pin down details at this time.
High temperatures are forecast in the 80s on Friday and Saturday,
followed by a warming trend Sunday (near 90 degrees) and Monday
(90s region-wide). Tuesday and Wednesday look slightly cooler in
the upper 80s to low 90s. Low temperatures range in the upper 50s
to upper 60s throughout the period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 542 PM MDT Wed Jul 31 2019
VFR conditions anticipated through this evening. However, things
should change by tomorrow morning as low level moisture moves into
the region through the northeast surface flow. Anticipating MVFR
conditions due to stratus. There could also be some reduced
visibility from fog but confidence in this wasn`t too certain at
the moment. This may need to be adjusted later this evening. Other
concern to discuss is thunderstorm chances. There may be an
isolated storm near KGLD this evening so inserted a brief VCTS
period. Tomorrow evening, expecting a larger complex of storms to
move across the forecast area which would likely impact KGLD. KMCK
may be on the edge. Other than some brief gusty northeast winds
this evening, no other aviation concerns are expected.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...RRH
SHORT TERM...VINCENT
LONG TERM...JBH
AVIATION...RRH
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