Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/15/24
Area Forecast Discussion
National Weather Service La Crosse WI
1045 PM CDT Sun Apr 14 2024
.KEY MESSAGES...
- Still dry area-wide and becoming breezy Monday west of the
Mississippi River with elevated fire weather conditions.
- A potent spring storm to bring widespread rainfall (60-100%
1"+), strong winds and the potential for severe weather to
the area Tuesday and Wednesday.
- Chance for precipitation Thursday then a more seasonable to
end the week into the weekend. Cold lows Saturday morning
could lead to frost/freeze; damage to vegetation.
&&
.DISCUSSION...
Issued at 250 PM CDT Sun Apr 14 2024
Overview:
Water vapor satellite imagery and heights show a 500mb ridge of high
pressure over the Rockies with a closed area of low pressure over
Nevada/California. Lightning was occurring with the storm
complexes over parts of the northeast U.S. and north of the
closed low over Oregon. Of note was the dry air south of this
closed low and the tropical mid and high level moisture
streaming across Baja and the southern U.S. Strong 110kt upper
level jets extended across southern Canada and from southern
California into Nevada. The 850mb thermal ridge is now shifting
south of the forecast area, but not before allowing most
locations to warm into the 70s and lower 80s today with low
relative humidity values 15 to 25% with good mixing due to the
northwest winds with gusts 20 to 30 mph.
Tonight into Monday:
Surface high pressure will dominate with the mid-level ridge
building in from the west. A broad area of mid-level warm air
advection increases across the Dakotas into Minnesota with parts of
the area under the influence of the right entrance region of the
jet. The surface front over the Plains lifts north as a warm front
Monday toward the mid-Mississippi Valley. During this time,
moisture transport is increasing through the Southern and Central
Plains. 850mb temperatures around 8-14 deg C are expected today and
similar temperatures 8-12 deg. C temperatures are forecast for
Monday. Forecast soundings show increasing mid and high level
clouds with weaker mixing, thus temperatures still above normal, in
the 60s to lower and mid 70s. Frontogenesis increases and lapse
rates steepen from the Dakotas into Minnesota with some of the
deterministic/hi-res models developing elevated showers/convection
in this area. The 14.15Z HRRR spills some low probabilities of
showers/convection into Buffalo and Trempealeau Co. by 20Z and
along I94 during the late afternoon and evening. Other hi-res
models hinting at this. Expect ACCAS to develop and could see
some showers, unsure how far southeast they will develop into
the local forecast area. Will include 10-20 pops to cover this.
Should these showers develop due to the forcing, they should
dissipate during the early evening.
A potent spring storm to bring widespread rainfall, strong winds
and the potential for severe weather to the area Tuesday and
Wednesday:
The closed 500mb low pressure over the Rockies moves into the
Western Plains Monday night, through the Mid-Missouri River Valley
Tuesday and eastward to the Mid/Upper Mississippi River Valley.
We still see very good general model agreement on the synoptic
pattern, with continued strength and track differences which
will affect the track of the surface low and the resultant
precipitation and severe weather potential. The upper low
continues to push through Tuesday night into Wednesday with
showers generally east of the area Wednesday.
Broad synoptic lift increases with the approaching low pressure
system. Upper level support increases with strong warm air and deep
moisture advection. We should see showers and thunderstorms
increasing across southwest Iowa Monday evening along the warm
front. The showers and storms will become more widespread across the
region Tuesday morning with continued strong moisture advection. The
left front exit region of the jet will also help support the showers
and storms as they move north. There is a ribbon of 40 to 50kts of
deep layer shear with the first band that lifts north. Freezing
level forecasts vary by model from 8500 to 10500, so cannot rule out
the potential for severe storms with elevated hail. Mean
GFS/EC/Canadian ensembles show limited CAPE available with 200-600
J/kg of SBCAPE increasing Tuesday afternoon with increasing deep
layer shear of 45 to 55kts. The potential for severe weather
continues to be 15 to 30% for parts of northeast Iowa and southern
Wisconsin based on the current storm track, instability, forcing are
expected. The greater risk for severe weather is still south of our
local area. With this being a dynamic system, we will continue to
monitor how far north the warm front will make it in the short term
as well at the potential for elevated storms north of the warm
front.
Welcome rains; strong winds:
The mean 14.00Z GFS/EC/Canadian ensembles show a 30 to 60%
probability of 1" or more of rainfall for 24hrs by 7am Wednesday.
Our current forecast is leaning toward the higher end of guidance
with widespread 1 to 2 inches across the forecast area. Precipitable
water values continue to forecast in the 200-275% normal range for
Tuesday. The NAEFS has PWAT 2 to 3 standard deviations above normal.
Forecast soundings become saturated with a warm cloud depth of 3km
and a storm movement possibly increasing to 40kts. With multiple
rounds of showers and convection, this faster movement would affect
rain total. We`ll continue to monitor the forecast, but the area
could take an inch or two, however short term heavy downpours could
result in minor hydro issues related to ponding on roads and filling
of poor drainage areas.
We continue to see strong east winds develop Tuesday with gusts 30
to 45 mph. As the surface low tracks toward the area Wednesday
morning, the winds decrease, but increase again Wednesday afternoon
from the northwest with 30 to 45 mph.
Precipitation chances for Thursday - Still colder for the weekend:
Low pressure if forecast to track across Canada Thursday with a cold
front pushing through Thursday. Showers are forecast with this
system, but snow could try to mix in as the system exits the area
Thursday night. Still more seasonable for the weekend with
temperatures from the upper 20s to the lower 30s Saturday morning.
Due to the mild temperatures being followed by freezing
temperatures, we have the potential for frost/freeze headlines
Saturday morning.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1045 PM CDT Sun Apr 14 2024
VFR conditions are expected to continue through the TAF period,
with some mid to high level clouds moving over parts of the
area. Light and variable winds will gradually shift more
northeast/east into the morning. Otherwise, east winds will be
on the increase late in the TAF period and into the day on
Tuesday with much gustier conditions forecast into Tuesday ahead
of an incoming low pressure system.
&&
.FIRE WEATHER...
Issued at 250 PM CDT Sun Apr 14 2024
We remain under the influence of surface high pressure Monday with
light north and east winds with low RH values area-wide.
However later in the day, easterly winds increase west of the
Mississippi River with gusts 15 to 25 mph. High temperatures
again top out in the 60s to mid 70s with minimum relative
humidity of 20-30%. Due to the stronger winds and the warmer
temperatures with drier air in place, elevated fire weather
conditions may develop over parts of southeast MN and northeast
Iowa during the day. Relative humidities improve Monday evening,
however wind gusts will actually strengthen with the
approaching storm system overnight.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...Zapotocny
AVIATION...EMS
FIRE WEATHER...Zapotocny
Area Forecast Discussion
National Weather Service Bismarck ND
951 PM CDT Sun Apr 14 2024
.KEY MESSAGES...
- Multiple rounds of showers and a few thunderstorms are
possible tonight through Tuesday. Severe weather is not
expected.
- Low afternoon humidity and gusty southeast winds may lead to
near critical fire weather conditions on Monday afternoon
across the south.
- Expect cooler temperatures starting on Tuesday and lasting
into the weekend. The coldest days will be Thursday and Friday
when highs will mainly range from the upper 30s to mid 40s.
- Some light snow is possible Wednesday night through Thursday
night, mainly across the north. Little to no accumulation
expected.
&&
.UPDATE...
Issued at 950 PM CDT Sun Apr 14 2024
Fairly quiet evening continues. Perhaps a few sprinkles are
still possible through the late evening hours for areas under
weak radar returns. As a push of warm air advection sets up
overnight more shower activity is expected to develop, mainly
after midnight. This shower activity could then continue into
Monday. MUCape is still adequate for thunder, which will also be
aided by steepening mid level lapse rates. The LCLs will remain
quite high, and effective layer shear will be only be modest.
Thus severe weather is still not expected with this initial
round. Maintained NBM thunder chances for now, although thunder
could be found to a more broad area tonight through the day
Monday than currently in the forecast. Confidence was not high
enough to expand thunder mention at this time.
UPDATE
Issued at 700 PM CDT Sun Apr 14 2024
Little needing updating early this evening. Radar continues to
show light returns across central and northern portions. Dry air
in place has limited these to mainly virga showers. Chances will
increase for precipitation tonight, although current though is
this could delay until after midnight local time. Limited PoPs
to just sprinkle mention through the evening. Otherwise the
forecast remains on track.
&&
.DISCUSSION...
Issued at 300 PM CDT Sun Apr 14 2024
Western and central North Dakota currently sits under the
eastern slope of a low amplitude upper level ridge. Later
tonight, the ridge axis will move into western North Dakota as a
surface low starts to deepen to the east of the Rockies. Some
warm air advection showers will develop tonight and into Monday
morning, pretty much along the ridge axis and surface baroclinic
zone. RAP forecast soundings suggest the potential for 100 to
200 J/kg MUCAPE so a few rumbles of thunder are not out of the
question.
The main story for Monday will be the return of breezy to windy
conditions and the potential for some near critical fire weather
conditions. By late morning winds will increase out of the
southeast with the strongest readings generally along the South
Dakota border. Sustained winds in the 25 to 30 mph range will be
possible with a couple gusts to 45 mph. With the southeast
surface flow, we will not be as dry as we have been in recent
days but we should still dip into the 20 to 30 percent range for
minimum relative humidity Monday afternoon across most of the
west and south. Where the best overlap is, we could see some
near critical fire weather conditions, generally as far west as
Adams, Hettinger, and Stark counties, over to Morton, Burleigh
and Kidder counties, and down to Dickey and LaMoure counties.
This pattern would be a bit more concerning if we had dry
northwest surface winds, but near critical fire weather
conditions certainly seem possible. Highs will range from the
lower 60s northeast to the mid to upper 70s southwest.
Monday night into Tuesday, an upper low kicks out into the
central Plains while the surface low moves into Nebraska.
Showers and thunderstorms should start to develop over the
higher terrain in eastern Wyoming and southeast Montana before
slowly moving into western North Dakota in the evening and into
central North Dakota overnight. As far as thunderstorm
potential, there will be some decent elevated instability
associated with this system. The latest RAP data suggests the
potential for MUCAPE ranging in the 500 to 1500 J/kg range by
late Monday evening, generally along and south of Interstate 94
(the higher MUCAPE values will be located near the South Dakota
border). 0-1 km shear values are forecast to be high, on the
order of 35 to 50 knots, but 0-6 km shear is only forecast to
max out around 25 knots in the same area. Thus, it seems most
of the shear will actually be present below any thunderstorms
that do form, limiting any severe potential. Some instability
may hang around across the south and east through the late
morning and into the early afternoon hours on Tuesday, but
should start to diminish through the rest of the day,
transitioning any thunderstorm activity to just showers. Tuesday
will also be the start the next cooling trend with highs
forecast in the 50s.
Most of the precipitation will move out Tuesday night into
Wednesday morning but there could be some lingering showers
north (with some snow flakes possibly mixing in). An upper low
will then move across Manitoba to our north on Thursday. In
previous days, models have shown this low a bit further south,
leading to some snow chances across much of the state. However,
there has been a northern trend over the past few model runs
and most of the precipitation is trending well north of the
International Border on Thursday. Still, we could see enough of
a glancing blow to bring at least some light snow to our north.
Little to no accumulation is expected. After the aforementioned
upper low moves off to the east, mainly dry weather is expected
Friday and through the weekend.
Thursday and Friday look to be the coldest days of the period.
On Thursday morning we will see lows ranging from the lower 20s
to lower 30s and on Friday morning we will see lows mainly in
the low to mid 20s. Highs on Thursday will range from the upper
30s northwest to the upper 40s southeast. Friday may be just a
touch cooler, ranging from the upper 30s to the mid 40s. While
it`s still a ways out, we could see the next warm up starting on
Saturday. Finally, breezy to windy conditions should prevail
every day of the week starting tomorrow.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 700 PM CDT Sun Apr 14 2024
VFR conditions are expected through the forecast period. Clouds
go on the increase tonight into Monday morning, with scattered
showers and perhaps a few thunderstorms possible. Confidence in
timing and location of these showers is still low to medium. For
now placed VCSH in TAFs with medium confidence later tonight
through Monday morning. Confidence was too low to include
precipitation mention in TAFS for Monday afternoon at this
time, although most sites will have at least a slight chance for
an isolated rain shower. As mentioned, non severe thunderstorms
are possible tonight through Monday. Confidence was not high
enough to include any TS mention at this time. Lastly, look for
southeast winds to increase on Monday. Some LLWS is possible in
the west as a result. Confidence was only high enough to place
in KXWA TAF for Monday morning.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Anglin
DISCUSSION...ZH
AVIATION...Anglin
Area Forecast Discussion
National Weather Service Boston/Norton MA
1009 PM EDT Sun Apr 14 2024
.SYNOPSIS...
Showers end overnight, along with gradual clearing. Dry and
seasonably mild Monday through Wednesday. Another unsettled
pattern develops late this week, with near normal temperatures
and a few chances for rain Thursday into next weekend.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
1005 PM Update:
Low pressure near the Poconos in northeast PA will continue to
ride ENE along an elongated frontal boundary from its center
northeastward into Southern New England through late tonight.
This should gradually shift the effective frontal boundary
southward into the southern waters as time goes on tonight.
Though we had a few lightning strikes in CT a few hours ago, the
bulk of convective activity has remained well to the southwest.
Radar showing a fractured line of scattered showers located just
south of the Route 2 corridor, which will slowly progress
southeast toward the southern coastal waters thru midnight.
That will likely be the extent of it though over much of the
land with dry weather for the 2nd half of the overnight,
however it is possible we could see a rogue, garden-variety TS
develop over the southern waters (perhaps near MVY/ACK?) early
overnight per the HRRR and 18z/14th NAM-3km guidance. Rain amts
probably won`t amount to much more than a tenth of an inch as
showers should be passing and of generally light intensity.
Though the frontal boundary will be slowly sagging southward for
the 2nd half of the night well into the waters, cloud cover
could be a little slower to erode especially if the boundary
slows down. Did bump cloud cover up somewhat across the southern
half of Southern New England thru the pre-dawn hrs, essentially
a slower erosion of cloud cover. Further inland though, most
areas should trend mostly clear by overnight/pre-dawn period.
Previous Discussion...
A disorganized frontal wave will traverse over the Northeast
this afternoon and evening with scattered showers and a perhaps
a few thunderstorms. Latest SPC meso-analysis reveals no
significant surface based CAPE over southern New England within
the warm sector of the wave of low pressure moving through the
region. However, steep mid-level lapse rates are contributing to
elevated instability that could support a few rumbles of thunder
across western MA/CT and possibly over some locations near the
south coast this evening. Areas along and north of I-90 are
forecast to be in the cool sector, thus not expecting any
thunderstorm activity north of that mark. Any remaining showers
and thunderstorms are forecast to clear to the south and east
around or just before midnight. Thereafter we can expect gradual
clearing with winds shifting to the west/northwest. Low temps
bottom out in the low 40s across northwestern MA and mi to upper
40s elsewhere.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Tomorrow
A dry surface cold front pushes through the region during the
day tomorrow. This will support dry conditions and
west/northwest winds throughout the day. Skies will be clear to
start which will allow surface temps to warm to the upper 60s to
near 70 in some locations by the mid-afternoon hours. After a
sunny start, we will begin to see increasing diurnal cu during
the afternoon thanks to steep low- level lapse rates from cooler
air aloft. Overall a warm/dry afternoon. Warmest temps will be
focused in the CT River Valley and over southeastern MA where
downsloping from WNW winds should help temps over achieve.
Tomorrow Night
Very quiet tomorrow night. Clear skies and light west/northwest
winds. There is some question as to whether or not the
atmosphere decouples overnight. This will govern how far
temperatures are able to fall with radiational cooling. Will
have a better idea by tomorrow, but for now have leaned on a
blend of CONSMOS and NBM for low temps in the low to mid 40s on
Tuesday morning.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Highlights:
* Broad trough settled over the region for much of the upcoming
week, with a brief period of mid level ridging in the Tuesday-
Wednesday timeframe
* Near to above normal temperatures, with an unsettled pattern
developing late this week
Based on the latest guidance suite, still have the greatest
confidence in the forecast details into early Wednesday. After
then, there is little consistency with the timing and amplitude
of some synoptic features, leading to low confidence in the
forecast details. Kept a broad period of unsettled weather from
late Wednesday into Saturday, but not expecting this to be a
total washout this entire time. Expecting it will be a couple
more days before these details come into better focus. All that
said, there has been a consistent signal for near to above
normal temperatures through this portion of the forecast.
High pressure dominates our weather Tuesday into Wednesday.
Thinking we could get through most of Wednesday dry, especially
across the eastern half of southern New England. Just a low risk
for some showers during the afternoon farther west. More likely
to see rainfall arrive some time Wednesday night into Thursday
as a low pressure moves into the Great Lakes, with a secondary
low pressure possibly developing toward the Mid Atlantic coast.
This should move offshore Friday, with a lingering cold front
into Saturday. A large high pressure over the northern Plains
states should become more of a factor in our weather some time
Sunday.
Moisture is not particularly impressive, so not expecting a lot
of rainfall during the second half of this week. This should be
a good thing, by permitting area waterways a chance to drain
further.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Forecast Confidence Levels:
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High- greater than 60 percent.
Tonight...High Confidence.
VFR. Any remaining SHRA diminish after 03Z across most of the
region. Some SHRA may linger near the south coast of RI/MA
through about 08Z. This will be followed by some gradual
clearing from west to east through 12Z. Southwest winds becoming
northwest from 5 to 10 knots.
Tomorrow...High Confidence.
VFR. W/WNW winds around 10 knots. Some gusts up to 20 knots
possible.
Tomorrow Night...High Confidence.
VFR. Steady WNW winds continue.
KBOS TAF...High confidence in TAF.
KBDL TAF...High confidence in TAF.
Outlook /Tuesday through Friday/...
Tuesday: VFR. Breezy.
Tuesday Night: VFR.
Wednesday: VFR. Slight chance SHRA.
Wednesday Night: VFR. Chance SHRA.
Thursday: VFR. Breezy. Chance SHRA.
Thursday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Friday: Mainly VFR, with areas MVFR possible. Chance SHRA.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Tonight
Some showers and possible a rumble of thunder possible over the
south coastal waters before midnight tonight. Otherwise, expect
gusty southwest winds to diminish as winds shift to the
west/northwest overnight. Sustained speeds fall to 5 to 10 knots
by tomorrow morning with gusts less than 20 knots. Seas begin to
subside but remain high enough to warrant Small Craft Advisory
headlines for the outer marine zones.
Tomorrow and Tomorrow Night
Seas continue to subside to sub-Small Craft Advisory criteria by
tomorrow evening. Otherwise, expect relatively quiet conditions
over the coastal waters with modest 10-15 knot west/northwest
winds.
Outlook /Tuesday through Friday/...
Tuesday: Winds less than 25 kt. Seas locally approaching 5 ft.
Tuesday Night through Wednesday: Winds less than 25 kt.
Wednesday Night: Winds less than 25 kt. Slight chance of rain
showers.
Thursday through Friday: Winds less than 25 kt. Seas locally
approaching 5 ft. Slight chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 2 PM EDT Monday for ANZ232>235-237-
250.
Small Craft Advisory until 8 PM EDT Monday for ANZ254>256.
&&
$$
SYNOPSIS...Belk/RM
NEAR TERM...Belk/Loconto/RM
SHORT TERM...RM
LONG TERM...Belk
AVIATION...Belk/Loconto/RM
MARINE...Belk/Loconto/RM
Area Forecast Discussion
National Weather Service Cheyenne WY
540 PM MDT Sun Apr 14 2024
.KEY MESSAGES...
- Critical fire weather conditions are possible across the
southern Nebraska Panhandle Monday where Red Flag Warnings are
in effect from noon to 7 PM for gusty winds and low humidity.
- The next storm system will arrive Monday afternoon and bring
showers and thunderstorms followed by strong winds to portions
of the area. Accumulating snow is expected in the mountains,
and snow may mix in for the higher valleys and plains of
southeast Wyoming Monday night into Tuesday.
- Strong cold front associated with a large system across
central Canada will bring much colder temperatures and the
chance for valley snows Wednesday into Friday.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 340 PM MDT Sun Apr 14 2024
You name it we got it in the upcoming days with critical fire
weather...strong winds...winter weather and possible severe
convection all possible.
Currently...Stationary boundary lays along the front
range...north to the Laramie Range to a 1008mb surface low near
Buffalo Wyoming and finally into eastern Montana this
afternoon. Fairly quiet right now across southeast Wyoming and
Nebraska Panhandle. Off to the west...a Pacific low pressure
system has finally moved onshore across central California and
this will be the major contributor to our active weather
upcoming.
This low ejects inland overnight into southern Nevada and
eventually to central Utah by 12Z Monday morning. 700mb low
located across north central Colorado by mid afternoon Monday
with an almost vertically stacked 500mb low. Surface low located
just south of Sidney by 21Z Monday. Very dry air near the
surface low with 850mb winds 25-35kts out ahead of the low. With
the very dry air and strong winds...though it was prudent to
issue a Red Flag Warning for the southern Panhandle from noon to
7PM Monday.
To the northwest of this low...northwest winds forecast to
increase significantly Monday afternoon and evening. GFS
750/800mb winds up near 50kts across the Summit into Laramie
County Monday afternoon. GFS 700-800mb winds become stronger and
more widespread Monday evening into Tuesday morning. They peak
Tuesday morning near 55-60kts along and east of the Laramie
Range into the southern Nebraska Panhandle. Similar set up to
the wind storm we had a week or so ago. With that in
mind...decided to expand the High Wind Watches east into the
southern Panhandle.
Guidance consistent with increasing QPF and PoPs across our
western zones and especially the north facing slopes of the
Snowy and Sierra Madre Ranges. Getting anywhere from 17 to 24
inches in the mountains out west from 18Z Monday to 21Z Tuesday.
Decided to issue a Winter Storm Watch for the western
mountains.
Finally...there is a risk for severe thunderstorms Monday
afternoon and evening. HRRR and RAP simulated radar showing
convection continuing into the evening and past midnight across
our northern forecast zones into the northern Nebraska
Panhandle. NAM MUCAPE across Niobrara County into the Nebraska
Panhandle on the order of 1500-2000 J/KG from 21Z through the
evening hours. By far our best instability so far this spring.
Steep mid level lapse rates of 9C/KM across the Panhandle Monday
afternoon SPC maintains a Marginal Risk area from Sidney to
Torrington to just west of Lusk and a small sliver of Slight
Risk in Dawes County for Monday afternoon and evening. So can
not rule out a couple severe thunderstorms for Monday afternoon
and evening.
Upper low finally shifts east Tuesday afternoon with the wrap
around moisture shifting east as well. Upper level ridging
moves in from the west and we should see drying and warming
conditions by that time.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Issued at 340 PM MDT Sun Apr 14 2024
An extended period of active weather is expected for much of
southeast Wyoming and western Nebraska on the back side of the early
week system. Upper-level diffluence is progged to move overhead
Wednesday as the upper-level jet strengthens behind and swings in
from southern Canada. Zonal flow will develop late in the day as the
upper-level trough flattens out, placing the CWA underneath the
favorable right entrance region of the upper-level jet.
Precipitation chances will increase throughout the day Wednesday as
a 700mb cold front and an accompanying surface cold front push into
the region from the northwest. Some differences exist between the
long range models as to how much precipitation will fall with this
front. The GFS is a bit more bullish on precipitation for Wednesday
night into Thursday, while the ECMWF is slightly lower. The
differences appear to stem from the models suggesting that a surface
low will try to develop across southeastern Colorado during the day
Wednesday. The ECMWF suggests that this low develops and quickly
moves off to the east as the low is picked up by the upper-level
flow, decreasing the total precipitation expected. The GFS on the
other hand suggests that the surface flow attempts to develop, but
is slower. The surface low in the GFS develops before being pushed
south by the encroaching cold front and is flattened into a surface
trough rather than a closed low. The slower GFS solution would
result in more precipitation across the region, with the surface
trough sticking around longer than the more progressive ECMWF
solution. Despite these differences, both models suggest that after
another warm day Wednesday, colder temperatures will return for
Thursday onwards.
Colder air is expected to remain over the region Thursday through
most of the weekend as the CWA will be influenced by the broad,
upper-level trough of Canada. 700mb temperatures remain in the -5 to
-10C range once again, leading to daytime highs only in the 40s for
Thursday through Saturday. The region will be broadly within the
right entrance region of the upper-level jet for much of the end of
the week into the weekend, leading to continued synoptic support
across the region favoring the development of rain and snow shows
after the main push of showers from the cold front Wednesday night
into Thursday. In addition to this, several 500mb vorticity swaths
will traverse across the region leading to favorable cyclonic
vorticity advection to further support continued lift. Daily chances
for rain and snow showers are expected from Thursday throughout
Saturday with temperatures only reaching the 40s area wide.
A brief warm up is expected on Sunday as a relatively small, upper-
level ridge builds over the region ahead of the next incoming
system. The ridge will bring an end to the shower chances across the
region and allow temperatures to warm back into the 50s and 60s area
wide. Exactly how long this warmth will last is uncertain at this
time as the ECMWF and GFS suggest very different solutions. The GFS
suggests the upper-level ridge builds ahead of an incoming upper-
level low that is over the Pacific Northwest early Monday morning.
This system would be expected to bring cooler temperatures to the
region with the possibility of some precipitation. The ECMWF at this
time suggests no upper-level trough at all, instead suggesting the
upper-level ridge is the dominate feature that remains over the
western CONUS for several days. This will need to be monitored as
the ECMWF and GFS likely come into better agreement over the next
several days.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 540 PM MDT Sun Apr 14 2024
Upper level ridge axis will shift east into the Great Plains tonight
as the next storm system moves eastward over Utah and into western
Colorado Monday morning. Precipitation associated with this next
storm system unlikely to impact the area until after 00z Tuesday.
HAZARDS/WEATHER TRENDS: VFR conditions will continue tonight through
noon (18z) Monday. Although gusty winds will briefly subside this
evening, a strong low level jet will develop across the plains
between 02z and 06z...resulting in wind gusts as high as 40 knots
between 04z and 12z Monday across the western Nebraska terminals and
possibly KCYS. These winds may not always mix to the surface, so
left LLWS at each terminal.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Watch from late Monday night through Tuesday
afternoon for WYZ101-107-108.
Winter Storm Watch from Monday afternoon through Tuesday
afternoon for WYZ112-114.
High Wind Watch from Monday afternoon through Tuesday
afternoon for WYZ116-117.
High Wind Watch from late Monday night through Tuesday
afternoon for WYZ118-119.
NE...Red Flag Warning from noon to 7 PM MDT Monday for NEZ436-437.
High Wind Watch from Tuesday morning through Tuesday evening
for NEZ019>021-054-055.
&&
$$
SHORT TERM...GCC
LONG TERM...AM
AVIATION...TJT
Area Forecast Discussion
National Weather Service Dodge City KS
1029 PM CDT Sun Apr 14 2024
...Updated Aviation...
.KEY MESSAGES...
- Fire danger/severe weather possible on Monday
- High winds and blowing dust likely on Tuesday
- Temperatures trending cooler towards the end of the week
&&
.SHORT TERM /THROUGH TUESDAY/...
Issued at 200 PM CDT Sun Apr 14 2024
18z observations and RAP upper air analysis show a large upper
low spinning through much of California and Nevada with the jet
stream ahead of the low producing a ridge in the central plains.
This has led to plenty of sunshine all across the region.
Afternoon temperatures have already reached into the upper 80s
to lower 90s and Dodge City has already set a record high of 92
(as of this discussion) at 1 PM.
Tonight the upper low will track into central Utah and the nose
of the jet streak will move into central Colorado which will
start to deepen a surface low in northeast Colorado to around
998 mb by sunrise. Winds at the surface in response to the low
will start to turn more to the south to southeast and moisture
advection into our eastern zones should bring in an area of
stratus clouds and dewpoint temperatures reaching into the upper
50s to lower 60s. With the areas of moisture in our eastern
zones lows should fall into the mid 50s to lower 60s and lows in
the west will fall into the 40s.
Monday the main topic of interest will be the fire danger, wind,
and areas of patchy blowing dust. Fire threat looks greatest
along and west of highway 283 where a red flag warning is in
effect. Winds will increase through the day as the surface low
deepens in northeast Colorado to 989 mb and the nose of the
upper jet will enter into southwest Kansas by the late
afternoon. Wind speeds should increase to 20-30 mph with gusts
to 40 mph and humidity values will fall to 10%. With such dry
soils this will also lead to another good setup for some blowing
dust. East of 283 the moisture should stick around much of the
day to mitigate the fire danger somewhat.
Monday night will be the main time of the severe threat. At this
point there is low confidence in the amount and coverage of
storms but high confidence that any storms that develop will
become severe. Many of the short term models and ensembles are
showing the greatest lift with the upper low will be moving in
around 9-10 pm. The low level jet will increase after 7 pm and
advect moisture to the northwest that the dryline should retreat
to somewhere between US 283 and K-23 corridors. Many of the CAMs
are struggling with initiating storms along the dryline until
after 10 pm and perhaps closer to midnight. Any storms that do
develop will have plentiful 0-6 km shear (>50 kts) and CAPE
(>1500 j/KG) that large to giant hail can be expected with any
storm along with strong winds and an isolated tornado. The storm
mode will most likely be briefly supercell and then quick
upscale growth into a squall line along the dry line. Time frame
of storms between US 283 to the US 281 corridors will be
between 10 pm and 3 am. With the way the setup is looking at
this point there is at least 30-40% chance we may not see much
if any storm activity at all given how many short term models
and CAMs are struggling to initiate convection. With the quick
movement of the dry air from west to east we should be done with
storm activity by 3 am.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Issued at 223 PM CDT Sun Apr 14 2024
Tuesday will present a high likelihood of strong northwest
winds with high wind criteria possible. Through the day on
Tuesday the surface to 500 mb low will slowly move through
southern Nebraska and a sharp pressure gradient will be across
western Kansas especially for areas along the Colorado border.
EPS and GEFS ensembles have 100% chance of sustained winds over
20 kts and wind gusts over 34 kts are also at 100% with wind
gusts reaching high wind criteria (50 kts) at 30-40% for areas
along and west of highway 83. Given the strong winds and dry
soils another round of blowing dust will be possible all day
long. Lift along the western side of the low could also lead to
some spotty rain showers mainly along and north of K-96 however
rainfall totals should stay under 0.1 inch (> 90% chance).
For the rest of the week the trend will be cooling temperatures
and perhaps at the end of the long term some frost Sunday
morning. A large upper low in the Canadian prairies will
overspread colder air through the northern and central plains
Thursday through Sunday. With some 700 mb shortwaves and cold
fronts there are some small chances of rain (~20%) along and
north of I-70 on Thursday and across western Kansas on Saturday.
For Sunday the long range ensembles have 0% chance of
temperatures falling below 32 for Sunday morning however the
NBMv4.1 is picking up on a cold high pressure center in the
central plains and clear skies and has put in lows at 30-32
along and north of a Liberal to Larned line so we will have to
monitor to see if the growing season will be getting a mid-late
April frost.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1029 PM CDT Sun Apr 14 2024
VFR will continue through this TAF cycle. Light SE winds will
prevail through 15z Mon. After 15z Mon, strong south winds will
impact aviation operations at all airports, gusting 35-40 kts.
Limited reductions in visibility are expected in blowing dust
at/near GCK/LBL, but left out of this set of TAFs. All airports
will remain dry through 00z Tue. Rapid development of
thunderstorms is probable during the 03-06z Tue time frame, in
the vicinity of DDC/HYS along the dryline. Confidence is only
high enough to included a CB/VCTS mention at the end of the
DDC/HYS TAFs for now.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon CDT /noon MDT/ to 8 PM CDT /8 PM
MDT/ Monday for KSZ030-043>045-061>064-074>078-084>088.
&&
$$
SHORT TERM...Tatro
LONG TERM...Tatro
AVIATION...Turner
Area Forecast Discussion
National Weather Service Morristown TN
1006 PM EDT Sun Apr 14 2024
...New UPDATE...
.UPDATE...
Issued at 1002 PM EDT Sun Apr 14 2024
This evening, temperatures have been warmer than expected, and dew
points have remained lower than expected. This has been due to
both the strong mixing during the day, some cloud cover, and
remaining winds. As such, temperatures were raised slightly, and
dew points were lowered slightly for the overnight period.
Overall, this is a minimal change with remaining elements updated
based on the latest high-res guidance.
&&
.SHORT TERM...
(This evening through Monday)
Issued at 252 PM EDT Sun Apr 14 2024
Key Messages:
1. Warm temperatures continue through tonight and tomorrow.
2. Chance of thunderstorms in northern sections Monday afternoon.
Discussion:
Gusty SW winds have developed this afternoon in many spots with a
well mixed boundary layer bringing winds aloft to the surface. With
sunset and stabilization, we should see winds drop off. Winds may
remain a bit strong in the mountains as winds at the 850 mb level
will be around 30-40 kt, but not likely widespread enough for an
Advisory.
A front will be stalled north of the area, across northern
KY/central WV. Models are trending toward showing convective
activity along this front, notably in the HRRR and the ARW, with a
SE movement into SW VA. The NAM is an outlier and shows nothing
developing, likely due to a very strong capping inversion in is
forecast soundings. Will follow the consensus and have slight to low
chance PoPs in SW VA and NE TN tomorrow afternoon. Warm temperatures
will continue again tomorrow with highs in the upper 70s to mid 80s
with a SW low level flow and nearly full sun.
&&
.LONG TERM...
(Monday night through next Sunday)
Issued at 252 PM EDT Sun Apr 14 2024
Key Messages:
1. Chance of showers and storms Monday night into Tuesday.
2. Increasing rain chances with showers and thunderstorms Wednesday.
A break in the rain now Thursday. Rain chances and more storms
Friday and Friday night.
3. Turning cooler Saturday and Sunday behind front. Lingering rain
chances for the weekend.
Discussion:
On Monday night a weak surface front tries to slip southwestward
from the central Appalchians. But may not quite make it. Just south
of the front expect increasing clouds and some isolated showers and
storms Monday night into Tuesday southwest Virginia and northeast
Tennessee. Then late Tuesday or Tuesday night the front to the north
will shift north again as ridging strengthens temporarily. A
deepening low pressure over the plains and associated cold front
will be pushing eastward building the ridge Tuesday night into
Wednesday morning. This system will spread more clouds and showers
into the western sections late Tuesday night into Wednesday morning.
As instability increases expect thunderstorms to develop by
afternoon. Some stronger storms are possible just west of the area
Wednesday.
The front will push through Wednesday night but still expect another
front to develop behind it. This may allow the southeast ridging to
restrengthen with little chance of rain Thursday. Then the 2nd front
arrives Friday and Friday night moving slower than the first one.
There could be some strong to severe storms Friday. A prolonged
chance of showers and a chance of storms will keep the weekend
unsettled and become cooler both Saturday and Sunday. Trends now
keep lows above 50 Saturday and 40 Sunday mornings with the clouds
and lingering rain chances.
&&
.AVIATION...
(00Z TAFS)
Issued at 659 PM EDT Sun Apr 14 2024
The main aviation impact will be low-level winds overnight.
Breezy conditions at the surface are expected to decrease to 10
kts or less in the next hour or two with winds around 2,000 to
3,000 feet AGL remaining 30 to 40 kts overnight. As such, the
LLWS was maintained until about 11Z to 12Z when these low-level
winds decrease to around 20 kts. Overnight, fairly limited mid to
high clouds are expected. During the day on Monday, a persistent
southwesterly wind is expected with gusts to 20 kts or more
possible. There is a low-end chance for showers and storms late in
the afternoon around TRI, but this was left out of the TAF for
the time being. Otherwise, VFR is expected with most clouds at or
above 4,000 feet AGL.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 56 85 59 82 / 0 0 0 0
Knoxville McGhee Tyson Airport, TN 59 82 59 82 / 0 10 0 0
Oak Ridge, TN 56 83 58 82 / 0 10 10 0
Tri Cities Airport, TN 54 79 57 80 / 0 30 20 20
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
SHORT TERM...DGS
LONG TERM....TD
AVIATION...DGS