Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/01/20
Area Forecast Discussion
National Weather Service Bismarck ND
1050 PM CDT Sun May 31 2020
.UPDATE...
Issued at 1049 PM CDT Sun May 31 2020
Will allow the severe thunderstorm watch to expire. A few stronger
storms remain possible, but the main severe weather window has
closed.
UPDATE
Issued at 1002 PM CDT Sun May 31 2020
Thus far all shower/storm activity in ND has remained across the
southwest. This area of convection is projected to continue to
move easterly along the ND/SD border and as far north as I94 over
the next several hours.
Mid level forcing interacting with the sfc trough across eastern
Montana has resulted in thunderstorm development there, and is
projected to continue east into western ND over the next 1-2
hours.
Overall used a blend of the HRRR/RAP/ConsSHORT, but also had to
speed the eastward movement a tad with current activity outpacing
models by around an hour or so.
Severe thunderstorm watch remains in effect, and will reassess
over the next 45 min whether to let it go, which is likely as the
overall severe threat decreases.
UPDATE Issued at 804 PM CDT Sun May 31 2020
Have allowed the wind advisory across northwest ND to expire as
scheduled at 01Z.
UPDATE
Issued at 647 PM CDT Sun May 31 2020
The forecast for this evening remains on track. Severe
thunderstorm watch number 238 remains in effect for the
southwest.
Thunderstorms continue to move northeast across southeastern
Montana, and are projected to enter southwest ND between 00-01Z.
At this time, one severe storm tracking east of Miles City,
showing signs of being supercellular, taking a right mover track
more easterly versus northeast. Still some uncertainty on the
overall storm coverage across western ND with forcing aloft not
that impressive.
Will maintain the wind advisory as is but should be able to let it
expire within the next hour.
UPDATE
Issued at 511 PM CDT Sun May 31 2020
Severe thunderstorm watch now in effect for portions of southwest
North Dakota. Will update all products to reflect this.
&&
.SHORT TERM...(This evening through Monday)
Issued at 247 PM CDT Sun May 31 2020
The main concern for the short term period is the potential for
strong to severe thunderstorms in western North Dakota this evening.
An upper level ridge axis sits over the Northern Plains early this
afternoon, with a 30-40 kt low level jet underneath. Surface
analysis shows high pressure over the Great Lakes and a deepening
low in southern Alberta. This setup has resulted in windy conditions
across the region. The strongest winds have been in northwest North
Dakota, where sustained wind speeds over 30 mph have routinely been
reported. A Wind Advisory is in effect for that area until 8 PM CDT.
Mid level shortwave troughing will move into eastern Montana late
this afternoon as a surface trough sharpens attendant to the
southern Alberta surface low. The presence of additional forcing in
the form of low level frontogenesis is forecast across eastern
Montana. Most guidance agrees that convective initiation will occur
in eastern Montana late this afternoon, though some of the forcing
mechanisms appear a bit disjointed spatially. Additionally, recent
guidance suggests convective inhibition will be much weaker across
eastern Montana than originally thought, owing to a greater
likelihood of convective initiation given the forcing that is
forecast to be present. There is still some on uncertainty on
exactly where convective initiation may occur, but there is a
notable trend in more recent guidance to shift low level forcing as
far east as the ND/MT border by late afternoon. This can be seen,
for example, in RAP 0-1 km moisture flux divergence and theta-e
fields. However, there is greater convective inhibition and less mid
level forcing the farther east you go. This further contributes to
the uncertainty in the overall outcome of this event.
Surface based storms that develop will be in an environment
characterized by dewpoints around 60 F, CAPE around 2000 J/kg, and
30-40 kts of effective bulk shear, according to the HREF ensemble
mean. Shear vectors oriented nearly perpendicular to the surface
trough suggest a discrete mode will be favored initially, though
cold pool processes and sustained forcing mechanisms may eventually
lead to upscale growth into linear clusters downstream. A large hail
threat is supported by the aforementioned instability and shear,
storm mode, and relatively dry mid levels. A damaging wind threat is
supported by high LCLs and inverted-v thermodynamic profiles, as
well as by any transition to a linear mode.
There is general model consensus that at least isolated shower and
thunderstorm activity will continue to move across North Dakota
overnight as the surface trough and mid level shortwave track
eastward, though some of the more recent CAM runs have backed off on
this solution, likely due to increasing MLCIN. Quiet and warm
weather is expected on Monday as subsidence rebounds over the
Northern Plains. Highs will mainly be in the 80s.
.LONG TERM...(Monday night through Sunday)
Issued at 247 PM CDT Sun May 31 2020
Another mid level shortwave will approach western North Dakota
Monday night. There is decent model consensus for overnight shower
and thunderstorm development ahead of this wave, with forcing
possibly being aided by increasing low to mid level moisture
transport. If updrafts can take advantage of 1000-2000 J/kg MUCAPE
over southwest North Dakota, along with at least 40 kts effective
bulk shear, storms could become severe, with large hail being the
main threat. There is uncertainty on how much MLCIN will be present
though, which will be largely dependent on inflow layer RH. This
conditional severe threat may expand into south central North Dakota
Tuesday morning as the shortwave continues to propagate eastward,
but instability looks more marginal there. Farther north, scattered
showers are possible Tuesday morning in association with stronger
height falls, but there is expected to be little to no instability.
Model guidance has trended away from broad upper level ridging to
more of a zonal flow pattern late Tuesday through Thursday, with
various disturbances passing through. This pattern shift has
resulted in a slightly cooler temperature forecast through
Thursday, though still near to above normal. Long range guidance
appears to be converging on a solution that quickly builds upper
level ridging over the Northern Plains heading into the weekend
ahead of deepening longwave troughing over the Pacific Coast. This
could signal the beginning of an active period next weekend,
though deterministic models are exhibiting their known biases in
the progressiveness of the pattern, with the GFS being much
quicker to bring shortwave energy into the Northern Plains than
the ECMWF.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 647 PM CDT Sun May 31 2020
VFR conditions are expected through the forecast period. There is
a chance of thunderstorms in western ND this evening. This
potential shifts into central ND overnight, but with decreasing
probability. Left VCTS in the for KDIK, but opted to remove and
go with VCSH for KXWA, KMOT, KBIS and KJMS. If a storm does
happen to pass over a terminal, a brief period of MVFR/IFR
visibility and sporadic wind gusts would be possible. Strong
southeast winds around 20-25 kts gusting to 30-40 kts will
gradually decreasing this evening and overnight, with winds
shifting to the northwest for Monday.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...Hollan
LONG TERM...Hollan
AVIATION...NH
Area Forecast Discussion
National Weather Service Dodge City KS
545 PM CDT Sun May 31 2020
...Updated Aviation Discussion...
.SHORT TERM...(This evening through Monday)
Issued at 146 PM CDT Sun May 31 2020
The environment across southwest Kansas will be very similar to
the conditions yesterday evening. A surface boundary will be
located near the Colorado border into northeast Kansas with weak
shear and flow aloft. Late day and evening non severe convection
near this boundary will once again be possible but any of these
storms that do develop will move northeast and should not make it
far enough east to crossing into Hamilton or Stanton counties. As
for the chance for overnight convection much like last night
north of K96...the RAP does hint that some elevated convection
will be possible between 06z and 12z Monday east of highway 283.
This may not be an unreasonable solution late tonight given the
forecast mid level instability, weak 850mb-700mb moisture
transport and location of the 10-12c 700mb temperature gradient.
Will carry small <20% pops for convection tonight given that
moisture and the warm air advection forecast tonight does not
look as good as it did last night.
The overnight cloud cover from any convection that does develop
will give way to a sunny afternoon on Monday. Highs will once
again climb into the mid 90s across southwest Kansas. As the
warmer 850mb to 700mb temperatures air spreads east on Monday the
highs in the Hays, Larned, Pratt and Medicine lodge area are
expected to climb to around 90 degrees.
.LONG TERM...(Monday night through Sunday)
Issued at 146 PM CDT Sun May 31 2020
Models remain in good agreement with bringing only an increase in
mid to high level moisture into central and portions of southwest
Kansas Tuesday as an upper low slowly wobbles across north Texas
and Oklahoma. GFS continues to hint at maybe a few sprinkles or a
few light rain showers will be possible across south central
Kansas Tuesday night. Main impact will be some clouds late
Tuesday and the possibility of this keeping temperatures only in
the lower 90s...mainly for south central Kansas. Across western
Kansas the chance for afternoon clouds do not look very promising
and based on the 850mb to 700mb forecast temperatures at 00z
Wednesday the highs should easily climb into the mid 90s.
The Southern Plains upper low will move slowly towards Arkansas
and Missouri mid week as a series of upper level waves cross the
Central Rockies and move out into the West Central High Plains. As
each of these upper waves move east/southeast across the Central
Plains along the mid level baroclinic zone Wednesday night and
Thursday night there will be a chance for thunderstorms ahead of
each of these upper waves. At this time however the GFS and ECMWF
differ on exactly where this baroclinic zone will be located but
this morning`s model run seems to be trending towards northern
Kansas.
Warmer 850mb to 700mb temperatures are currently forecast to
spread across southwest late week with 700mb temperatures on
Friday forecast by both the GFS and ECMWF to warm to around 15C.
850mb temperatures are also forecast to be between 3-5C warmer
late week compared to the 00z Monday 850mb temperatures. This nice
warmup continues to support highs climbing into the upper 90s late
week and early this weekend with even the potential for a few
locations in southwest Kansas to see highs around 100 degrees.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 540 PM CDT Sun May 31 2020
VFR conditions will prevail for the entirety of the period for all
TAF locations. Gusty south winds will diminish after sunset around
03Z to around 15kts overnight. By 15Z, the leeside trough over
eastern Colorado will deepen due to diurnal trends mixing the low
level jet winds to the surface gusting up to 30kts lasting through
the end of the period through sunset once again. No other weather
elements expected at this time.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 92 63 94 / 10 0 0 0
GCK 62 93 63 96 / 0 0 0 0
EHA 62 93 62 95 / 0 0 0 0
LBL 61 93 62 95 / 0 0 0 0
HYS 65 93 65 94 / 20 0 0 0
P28 62 90 65 94 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Lowe
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
959 PM CDT Sun May 31 2020
.UPDATE...
Issued at 955 PM CDT Sun May 31 2020
Updated the forecast to include slgt chc for tstms, mainly for
areas along and E of Hwy 281. Hi-res models have hinted at this,
though are a bit slow with the development. This activity appears
to be tied to mid-level WAA as latest RAP forecast soundings
indicate a few hundred J/kg of MUCAPE from parcels based around
H6-H7, with little to no CIN. Thus, this activity appears to
independent of incr LLJ based closer to H85 per latest UEX VAD.
This activity should be largely SE of the CWA by around 12Z.
&&
.SHORT TERM...(This evening through Monday)
Issued at 334 PM CDT Sun May 31 2020
We have a few sprinkles across the area south of I-80 this
afternoon that are not being well resolved by the forecast models.
The clouds are also a bit thicker and more widespread than had
been indicated by most of our forecast models. Consequently, our
afternoon highs will probably be a few degrees cooler than
previously forecast. These sprinkles really should begin to
disappear with the loss of afternoon heating by early evening. We
then expect a generally quiet evening with perhaps some isolated
shower redevelopment after midnight as low level jet really ramps
up. Any showers late tonight, should be confined to an area
southeast of the Tri-Cities.
Monday...The upper level ridge will be centered over the plains,
which means hot weather will make itself felt as highs climb to
around 90 or the lower 90s. We expect more sunshine and the same
gusty southerly winds. Southerly wind gusts will likely once again
be around 30 mph from late morning through late afternoon.
.LONG TERM...(Monday night through Sunday)
Issued at 334 PM CDT Sun May 31 2020
Monday night through Wednesday...
The upper level ridge will spell continued dry weather until it
flattens out by a short wave Tuesday night. The best chance for
showers and thunderstorms Tuesday night will be across our
Nebraska zones. There will be a good deal of instability Tuesday
evening even though wind shear will be rather marginal so we could
see perhaps a marginal threat for severe weather. The frontal
boundary will push south of us Tuesday night so we will be cooler
and less windy north of the front on Wednesday.
Wednesday night through Friday...
We`ll have fairly zonal flow aloft while a sfc front slowly lifts
back north through our area as a warm front. Wind shear will be
very marginal with the upper jet stream well north of our area.
The frontal boundary will be in the neighborhood so we could see
some thunderstorms mainly along and north of this front as it
lifts north across the area and stalls out at times before finally
pushing all the way through. The severe weather threat appears
rather minor given the marginal deep layer shear values. We`ll
be in the cooler 80s on Wednesday but will start to warm back up
into the lower 90s by Friday as that front lifts north.
Saturday through Sunday...
It currently appears like a hot weekend with southerly winds at
the surface and a building upper level ridge aloft. Rain chances
if any appear rather low.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Tuesday)
Issued at 650 PM CDT Sun May 31 2020
Significant wx: Low level wind shear (LLWS) tonight.
Tonight: VFR. Main concern will be a strong jet (likely peaking
around 55-55kt) leading to LLWS at both terminals beginning around
03Z. Expect periods of SCT clds around 15K ft. Can`t completely
rule out an iso shwr/tstm, but only 10-20 percent chc so left out
attm. Sfc winds will remain elevated at 12-17kt, w/ gusts 18-22kt,
veering from the SE to SSW by dawn. Confidence: Medium to high.
Mon: VFR. LLWS expected to mix out around 13Z as sfc winds once
again incr. Expect peak SSW winds late morning thru early aftn at
15-20kt, w/ gusts 25-30kt. FEW to SCT high clds, at times.
Confidence: High.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...Thies
SHORT TERM...Wesely
LONG TERM...Wesely
AVIATION...Thies
Area Forecast Discussion
National Weather Service Goodland KS
534 PM MDT Sun May 31 2020
.SHORT TERM...(This evening through Wednesday)
Issued at 235 PM MDT Sun May 31 2020
Tonight-Monday night...low level convergence wind and moisture
convergence is expected to be maximized roughly along a line
extending from near McCook to Goodland and Kit Carson in the 5 PM
MDT to 7 PM MDT timeframe shifting slightly west to a Trenton to
Goodland and Cheyenne Wells line by 9 PM MDT based on the 15z RAP40.
As convergence is maximized convective inhibition should erode
enough to generate isolated to scattered thunderstorms. The primary
threats will be wind gusts to 60 mph and hail below one inch in
diameter. Given fairly slow storm motions some locally heavy rain is
also possible. Mid level moisture continues to rotate into the area
mentioned above after midnight around an upper level high pressure
center located in southeast Kansas. Precipitation chances should
come down fairly quickly leaving only some cloudiness.
As precip chances do decrease some hints from the 15z and 17z
HRRR suggest a heat burst type event possibly occurring based on
relative humidity values below 20 percent, weak showers and
localized potentially very strong wind gusts and much warmer
temperatures compared to their surroundings in or around Yuma,
Dundy, Cheyenne (KS) counties. Typically the 06z-09z timeframe
has had these events happen over the years and the HRRR was
suggesting one around 07z-08z. Low temperatures are expected to
fall into the upper 50s to mid 60s.
For Monday and Monday night a similar scenario. Mid level moisture
rotates into the northwest 1/2 of the area during time of peak
heating supporting slight chance pops for thunderstorms through mid
to late evening. High temperatures are expected to be in the low to
upper 90s. Low temperatures are expected to be in the mid 50s to mid
60s.
Tuesday...well see another chance for thunderstorms from late
afternoon through about midnight as mid level moisture and a little
better jet energy traverses east across the northern and western 1/2
of the forecast area. High temperatures are expected to be in the
upper 80s to mid 90s. Low temperatures again in the mid 50s to mid
60s.
Wednesday...the upper flow has shifted to a more west/west-northwest
flow around an upper high centered from Mexico toward the four
corners. Isolated thunderstorms will be possible in the afternoon,
primarily across far eastern Colorado. High temperatures look to be
a little "less hot" with readings in the mid 80s to low 90
.LONG TERM...(Wednesday night through Sunday)
Issued at 157 PM MDT Sun May 31 2020
Upper ridge will migrate from the desert southwest to start the
period, across the souther plains and into the Mississippi River
valley by the weekend. Proximity to the ridge will result in above
to much above normal temperatures. Thunderstorm chances, while
low, will be a daily occurrence in the afternoon and evening
hours, with best chances in western areas where storms may move
off the higher terrain of Colorado. Risk of severe chances will be
low as well, hampered primarily by deep layer shear values
forecast to be 20-25kts through the period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 534 PM MDT Sun May 31 2020
Vfr conditions are expected to prevail through the TAF period at
both KGLD and KMCK terminals. Southerly winds at 15 to 20 knots,
with gusts around 25 to 30 knots, are anticipated through the
evening before winds become south-southwest and lighten overnight
into early Monday. Isolated thunderstorms will be possible from
the start of the TAF period through about 03Z. However, confidence
in storms directly impacting the terminals was too low to insert
a mention at this time. If a storm did move across either
terminal, sub vfr conditions could occur. Regardless, an increase
in cloud cover can be expected this evening as storms develop in
the region, followed by clearing through Monday morning.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...99
LONG TERM...024
AVIATION...JBH
Area Forecast Discussion
National Weather Service Pueblo CO
303 PM MDT Sun May 31 2020
.SHORT TERM...(This evening through Monday)
Issued at 302 PM MDT Sun May 31 2020
Currently...
A line of showers and storms were noted along a sfc trough over the
plains from just SW of KLHX down towards KTAD. Isolated storms were
noted over the mountains and higher terrain, with the most
concentrated activity over the higher elevations of the Pikes Peak
region.
Dewpts this afternoon are several degrees less than y`day at this
time and there is no moisture boundaries noted over the plains.
Temps are also a bit cooler with 80s to L90s over the lower
elevations and about 80 or so in the larger valleys.
Rest of Today and Tonight...
Don`t expect the weather to be as active as yesterday given the lack
of forcing and llvl moisture over the region, however we still will
see scattered storms over the entire region, with the best activity
expected in the Pikes Peak region mainly later this afternoon.
Otherwise, expect partly to mostly cloudy skies over the area with
generally light winds. The exception will be over the far southeast
plains where gusty southerly winds of 20 to 30 mph will prevail.
As for tonight...scattered storms should wind-down later this
evening with min temps falling into the U50s and 60s plains...and
30s and 40s mtns/valleys.
Tomorrow...
Better moisture is expected to be over the ara tomorrow but flow
goes very weak at all levels. Storms to should be a bit more
widespread during the afternoon tomorrow but they are note going to
move much. This may lead to an actual increasing in localized flash
flooding, especially if storms plant themselves over a burn scar. In
general, the majority of the guidance was indicating the best chance
of heavier rain along the CONTDVD region, so will will have to watch
the Chalk Bluffs region (W of Buena Vista) closely. The 36h
experimental HRRR was indicating we may see storm motion in a east
to west component, and if this happens, the CONTDVD region may see
the greatest threat. Overall, tomorrow will have to be watched
carefully for a localized heavy rain threat. It should be noted that
HPC has a marginal risk of heavy rain over our region for tomorrow.
In the Ensemble guidance suite, both Q and PW are running rather
high over the fcst area during the afternoon time period.
In a nutshell, slow storm motion + Lots of liquid + CAPE (but no
shear) = localized heavy rain threat tomorrow. Where that threat
actually materializes still needs to be determined. /Hodanish
.LONG TERM...(Monday night through Sunday)
Issued at 302 PM MDT Sun May 31 2020
.Monday Night and Tuesday...Weak upper disturbance over Texas
will drift northward. On Monday evening, localized heavy rain
threat over the mountains will decrease as convection wanes.
Models hint at a weak surface trough, associated with the weak
upper disturbance, over the eastern plains Monday evening which
could be the focus for some convection. Increased the PoPs
somewhat Monday evening to have the mention of thunderstorms over
the plains. On Tuesday, the weak upper disturbance will tend to
keep the winds aloft from an easterly direction. The light
easterly winds may help to focus convection more over the eastern
mountains, and the NBM PoPs show this trend for Tuesday afternoon.
Weak features will determine where and if convection develops on
the plains Tuesday afternoon and evening. These weak features are
difficult to identity especially with convective parameterization
in the models. Winds aloft continue to be weak with the threat for
some locally heavy downpours, and will have to monitor the burn
scars. For now, did not touch the NBM PoPs which have PoPs
decreasing to near zero near the Kansas border.
.Wednesday and Thursday...Upper ridge develops with modest
westerly flow over the area. Still looks to be enough moisture in
the ridge for diurnal convection, mainly confined to the higher
terrain. There will be a gradual decrease in moisture which will
reduce the flash flood threat. A weak boundary may move southward
Wednesday, and current simulations do not show a stronger push of
moisture southward over the plains.
.Friday and Saturday...This looks to be an interested period.
Upper low off the California coast becomes an open wave and lifts
northeast across the central Rockies. Still some timing issues
between the models and ensembles. In general, the GFS and GFS
ensemble mean are faster than the EC and EC ensemble mean. There
could be significant synoptic scale lift associated with the
trough passage as well as increased wind shear. Will have to watch
for the potential for strong to severe storms with the potential
for some heavier rain. Current ensemble mean keep the best
synoptic lift over the mountains with lesser chances for
precipitation on the plains. There is still much uncertainty as
the movement of the upper lows is a difficult forecast.
.Sunday...After the upper trough passes, Sunday looks to be the
start of a period of generally warmer and drier weather.
--PGW--
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 302 PM MDT Sun May 31 2020
Best chance of storms for KCOS will be prior to 6 pm this evening.
Otherwise VFR through tomorrow, but we may see some more storms
tomorrow by mid afternoon.
KPUB and KALS...Isolated storms possible this afternoon/evening and
again tomorrow afternoon/evening otherwise VFR.
Winds all areas will be light and diurnal except gust in and around
TSRA
Any rain tomorrow afternoon could be briefly heavy for 15-30
minutes.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...PGW
AVIATION...HODANISH