Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/30/25
Area Forecast Discussion
National Weather Service Burlington VT
1024 PM EDT Sat Mar 29 2025
.SYNOPSIS...
A stationary front will lift to the north tonight, adding
significant freezing rain to southern portions of the region
while icy conditions also spread northward. Precipitation will
trend lighter with mainly freezing rain and plain rain as
temperatures rise on Sunday. The St Lawrence Valley and
sheltered hollows east of the Green Mountains will hold onto
sub-freezing temperatures during the day. Monday will be much
warmer with some showers, chances for thunder, and sharp river
rises, then a return to below normal temperatures will occur for
Tuesday following a cold frontal passage.
&&
.NEAR TERM /THROUGH MONDAY/...
As of 1019 PM EDT Saturday...Area of precipitation still
situated over our southern CWA border, and will slowly drift
northward overnight. Very tricky temperature forecast which
will have an impact on precipitation types. Have left PoP and
weather forecast as is. Previous discussion follows.
A long duration "winter" storm continues tonight as the front
that has sagged southward today begins to move northward
tonight. As this front moves northward, precipitation upstream
across the Great Lakes region will begin to fill in parallel to
the boundary. As such, precipitation will resume in the form of
freezing rain in the same areas that received as much as 0.5" of
flat ice (0.2" radial) this morning. As such, we went ahead to
issue an Ice Storm Warning through all of our southern zones -
south central Vermont across the Adirondacks and southern St.
Lawrence County.
It is important to note that as temperatures begin to warm
aloft tonight, large variations in conditions will develop over
short distances driven by topography. Increasingly high pressure
will build over the Gulf of Maine tonight, driving
southeasterly flow into eastern Vermont such that it is forced
up at the Green Mountains - this will lead to increasingly cool
air in the mid- slope areas, especially pronounced in Addison
and Rutland counties. This will be just one of many topographic
effects that will drive precipitation type between rain and
freezing rain through the period. Temperatures from a blend of
high- resolution HRRR and NAM3 continue to do better than any
bias corrected blend today and were used through this period,
which are intended to best capture areas that will stubbornly
stick to freezing rain. Based on timing of steady precipitation
at night, have some concern of very difficult travel overnight
before sunrise. Thereafter, most impacts due to ice should be
related to utilities and tree damage.
Steady precipitation will shift north of the area gradually
tomorrow, and while the surface front will still be to our south
overnight, some elevated scattered showers with a chance of a
rumble of thunder will begin to slide across the region. These
showers could still be in the form of freezing rain in localized
areas, but largely after dark tomorrow the threat of icy
conditions will be diminishing.
&&
.SHORT TERM /MONDAY NIGHT/...
As of 330 PM EDT Saturday...Much of Monday morning and
afternoon will be spent in the warm sector of the low pressure
system to our west and north. Warm air advection will allow
surface temperatures to rise to the upper 50s to mid 60s during
the daytime. Scattered rain showers will continue through the
morning. Continuing to note some brief instability Monday
morning, so have added mention of a slight chance of
thunderstorms to portions of northern NY Monday morning,
coincident with the best instability. Southwest winds during the
day will increase, especially aligned over the Saint Lawrence
Valley, where gusts will reach up to 30 mph during the
afternoon. Showers will then become more focused and briefly
more intense in the late afternoon/evening as a cold front moves
through.
With the warming temperatures Monday, expect much of the newer
snow in lower elevations to melt. This snowmelt, along with
additional QPF, will allow for some rapid rises in area rivers
Monday into Monday night. At this time, most rivers are forecast
to remain within bankfull, however the latest forecasts from
the Northeast River Forecast Center take the East Branch Ausable
River at Au Sable Forks and the Mad River at Moretown briefly
into minor flood stage near midnight Monday.
The front will continue to sweep through overnight, with
additional rainfall turning to brief snow in higher elevations.
Additional snow accumulations will be limited to just a few
tenths of an inch in higher elevations overnight before drier
air arrives and precipitation comes to an end by Tuesday
morning.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 330 PM EDT Saturday...Quiet weather is expected Tuesday
with surface high pressure to our north being in control. During
the day Tuesday, will see some cold air advection on the
southeastern periphery of the anticyclone, resulting in a chilly
day with highs only in the 30s. Winds will start off breezy
from the northwest during the morning, then slacken as the
center of the high moves closer and the pressure gradient
weakens. Overnight lows Tuesday night will be chilly as well
with favourable radiational cooling conditions. Have hedged
towards the colder side of guidance for this night, resulting in
lows in the single digits to teens.
Temperatures will warm Wednesday on return southerly flow
behind the departing cyclone. The next chance for widespread
precipitation will come Wednesday night through Thursday as a
low pressure system lifts northeastward out of the central US
and tracks into southeastern Canada. This system will initially
drag a warm front through our forecast area Wednesday night,
followed by a cold front Thursday afternoon into Thursday night.
Thermal profiles suggest another complex weather system in
terms of precipitation type, with ptype variable across the
area. Areas most likely to see predominantly rain out of the
system will be the Saint Lawrence Valley and the Champlain
Valley, while the higher elevations of the northern Adirondacks
and portions of eastern Vermont could see a wintry mix Wednesday
night before transitioning to rain. It`s still too early to
nail down thermal profiles, but more details will emerge as we
get closer to the event.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...Precipitation overspreads the region this
evening. It may briefly start as snow but it will mostly take the
form of freezing rain. This freezing rain will continue in most
places for the rest of the night before transitioning to rain as
temperatures rise above freezing during the day tomorrow. IT may
take until tomorrow night to transition to rain at MSS.
Precipitation will become more spotty later in the day. The snow at
the onset will cause a brief period of IFR visibilities and then
reduced visibilities are possible for the rest of the night and into
the day tomorrow from mist/drizzle. Ceilings will likely drop to IFR
once precipitation arrives and they will likley stay down until
winds increase significantly tomorrow afternoon and scour out the
low moisture, except at MPV and MSS where they might stay despite
the increased winds. LLWS develops late tomorrow. Winds are
generally light tonight, before becoming much stronger and s/se
during the day tomorrow. Gusts of 10-20 KTs are expected.
Outlook...
Sunday Night: Mainly MVFR, with areas IFR possible. Chance RA,
Chance SHRA.
Monday: Mainly MVFR, with local IFR possible. Likely SHRA.
Monday Night: Mainly MVFR, with local IFR possible. Chance SHRA,
Slight chance SHSN.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. Slight chance SHRA.
Wednesday Night: Mainly MVFR and IFR, with areas VFR possible.
Definite SHRA, Definite SHSN.
Thursday: MVFR/IFR conditions possible. Chance SHRA.
&&
.HYDROLOGY...
As of 400 AM EDT Saturday...Latest guidance continues to
suggest local rivers will experience modest to locally sharp
rises by late Sunday into Monday due to melting snow and
rainfall across the area. In general, current crest forecasts
indicate rivers most susceptible in reaching bankfull or minor
flood stage are the typical culprits, including Otter Creek, and
the Mad and Ausable rivers which are currently forecast to
crest at minor flood stage. At this time, probabilities of
reaching higher flood stages are quite low, so widespread,
highly impactful flooding is not expected. However, those with
interests in typical nuisance lowland flooding areas on these
and other rivers across the Adirondacks into central/southern
Vermont should monitor current and future forecasts related to
this event.
&&
.CLIMATE...
Heavy precipitation on Saturday could approach or exceed daily
records, as indicated below. As of 3 PM, the preliminary
precipitation at KSLK has set a new record at 0.64".
Date KBTV KMPV K1V4 KMSS KPBG KSLK
03-29 0.82|1888 0.71|1954 0.67|2020 0.84|2020 0.71|2020 0.62|1932
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory until 8 PM EDT Sunday for VTZ001-002-
004-005-016.
Ice Storm Warning until 8 PM EDT Sunday for VTZ009>011-018>021.
Winter Storm Warning until 8 PM EDT Sunday for VTZ003-006>008-
017.
NY...Winter Weather Advisory until 8 PM EDT Sunday for NYZ026>028.
Ice Storm Warning until 8 PM EDT Sunday for NYZ029-030-034-035-
087.
Winter Storm Warning until 8 PM EDT Sunday for NYZ031.
&&
$$
SYNOPSIS...Kutikoff
NEAR TERM...Kutikoff/Neiles
SHORT TERM...Duell
LONG TERM...Duell
AVIATION...Myskowski
HYDROLOGY...Hastings/Kutikoff
CLIMATE...WFO BTV
Forecast Discussion at weather.gov/mqt.
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Winter Weather Advisory until 1 PM CDT Sunday for MNZ034-036.
Winter Weather Advisory until 5 PM CDT Sunday for MNZ037-038.
WI...Winter Weather Advisory until 5 PM CDT Sunday for WIZ001.
Winter Storm Warning until 7 PM CDT Sunday for WIZ002>004-
006>008.
Ice Storm Warning until 7 PM CDT Sunday for WIZ009.
MARINE...Gale Warning until 5 PM CDT Sunday for LSZ121-140>148-150.
&&
$$
DISCUSSION...Unruh
AVIATION...Huyck
MARINE...Unruh
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
617 PM CDT Sat Mar 29 2025
...00z Aviation Update...
.KEY MESSAGES...
- Strong to severe storms possible late this afternoon into
late tonight, with large hail and damaging wind gusts being
the primary hazards.
- Much cooler temperatures expected for tomorrow and Monday.
- Strong to severe storms possible again Tuesday night into
early Wednesday morning.
&&
.DISCUSSION...
Issued at 223 PM CDT Sat Mar 29 2025
Current water vapor imagery overlaid with 500 mb heights and
winds shows a shortwave trough across the Central Plains, with a
longer wave trough across the Desert Southwest. At the surface,
a low is centered over north central Kansas with a cold front
and dryline extending southward and a stationary boundary
extending east northeastward through south central Iowa. Current
conditions across the region are defined by temperatures in the
70s with breezy south southeasterly winds (gusts up to 25 to
mph). By later this evening, the shortwave trough across the
Central Plains will translate ENE into the Upper Midwest, with
mid level height falls and a 40 to 45 knot mid level jet streak
overspreading the region. Meanwhile, the surface low is
projected to move into far NE Kansas by around 7 pm, with the
cold front extending to the south southwest across eastern KS.
Per the SPC HREF, a corridor of 1500 to 2000 J/kg of MU CAPE
should be in place along and ahead of the front, and with 40
knots of deep layer shear, well organized updrafts will be
possible with any storm that manages to initiate. The problem is
that some convective inhibition looks to hang on per model
soundings, and most recent HRRR guidance suggests that storms
this evening may have trouble sustaining themselves. That being
said, the 18z NAM NEST is quite different than the HRRR, and
develops robust convection across NE Kansas and NW Missouri by
around 6 PM. Large hail will be the primary hazard with these
storms late afternoon into this evening. CAMs have been quite
consistent in developing an MCS across northern Oklahoma by
around midnight tonight along the lagging portion of the cold
front, with this moving to the northeast and potentially taking
on the appearance of a bow echo as it nears the MO/KS border in
the vicinity of Fort Scott KS/Nevada MO by around 2 to 3 am
Sunday morning. This is projected to weaken as it heads further
NE into Missouri into a less favorable environment through the
early Sunday morning hours. The northern edge of this bow echo
could perhaps clip portions of our far southern and southeastern
counties, from Linn County KS to Cooper County MO (Pleasanton
KS to Boonville MO for those who are less county inclined). Any
stratiform rain behind the leading convective line should clear
by around 7 AM Sunday, with another round of some light rain
possible behind this later tomorrow morning. Temperatures will
cool behind the front tonight, with a midnight high likely for
Sunday across the region as temperatures only rebound a couple
degrees during peak heating tomorrow afternoon with breezy WNW
winds.
Cooler temperatures continue into Monday, with highs in the mid
50s with 10 mph northerly winds. Unsettled weather looks to
return on Tuesday afternoon/night, as mid/upper troughing is
progged across the western CONUS into the Plains, with very
strong southwesterly flow aloft overspreading the region.
Meanwhile, a deep surface low is projected to develop across
southern Nebraska, yielding strong theta e advection across our
region Tuesday evening. Strong to severe storms will be
possible Tuesday night into early Wednesday, and SPC has placed
most of our region within a 15% severe weather outlook. Any
lingering rain should clear east of the region by Wednesday
afternoon, with highs in the low to mid 70s.
&&
.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 613 PM CDT Sat Mar 29 2025
A somewhat tricky TAF period on deck here ... Of highest
confidence is MVFR ceilings coming in on the backside/behind the
cold frontal passage this evening and breezy conditions into the
low to mid 20s kts out of the NW during daytime tomorrow. Of
much lesser confidence are the storm and shower chances.
Guidance remains consistent in a broken line of storms early in
the TAF period, about 01z to 04z across the sites. Have opted
for a PROB30 in this instance to highlight the non-guaranteed
nature of the storms. Later, a bit after 06z, there is some
confidence in a cluster of storms moving out of OK/KS areas and
into SW Missouri. Northern periphery may result in SHRA/TSRA
clipping sites KIXD/KMKC/KMCI, with confidence lessening as you
travel northward.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...None.
KS...None.
&&
$$
DISCUSSION...Williams
AVIATION...Curtis
Area Forecast Discussion
National Weather Service San Francisco CA
845 PM PDT Sat Mar 29 2025
...New UPDATE, AVIATION, MARINE...
.SYNOPSIS...
Issued at 103 PM PDT Sat Mar 29 2025
Unsettled weather through the early half of the week with rain
starting late tonight. Some sun Sunday afternoon between scattered
showers. Additional rounds of showers Monday and Tuesday as the
system exits. Amounts on the lighter side. Trending much drier for
the middle week into next weekend.
&&
.UPDATE...
Issued at 845 PM PDT Sat Mar 29 2025
The center of a low pressure system is approx 500 miles west of
the Bay Area this evening. This low will move northeastward
reaching far northern California and the Pacific Northwest Sunday.
What we`re watching for our forecast area is an eastward advancing
warm front that is attached to the low that will bring rain and gusty
southerly winds to the Bay Area and north Central Coast late tonight
and Sunday morning. There`ll be lingering showers Sunday afternoon
into Sunday night along with a general decrease in winds late in
the day.
Currently KMUX radar and the NOAA S-band profiling radar at Cazadero
show light precipitation (hydrometeor classification is dry snow
since it`s above the freezing level) arriving from the west. The
precipitation is reaching as low as near 8 thousand feet before
evaporating according to the profiling radar. High aloft, where
it`s very cold, the leading edge of relatively warmer/milder air
has resulted in a warm frontal temperature inversion seen way up
at 16.5 to 17 thousand feet on this evening`s (00z March 30th)
Oakland upper sounding. This signature on the sounding is the
earliest arrival of Sunday`s eventual surface warm front and
associated weather. There is currently a large area of dry air
beneath the warm frontal temperature inversion down to approx 4
thousand feet, the precipitable water on the sounding was 0.40",
which is near the 25th percentile for late March.
&&
.SHORT TERM...
(This evening through Sunday)
Issued at 103 PM PDT Sat Mar 29 2025
Increasing cloudiness on the way this afternoon as the next storm
system moves in. Current visible satellite showing solid cloud
cover just off the West Coast, which will begin affecting the land
area through this evening. Overnight temperatures tonight are
expected to be a bit warmer than last night due in part to
increased cloud cover and the approaching warm front associated
with the surface low. Rainfall associated with the warm front will
gradually fill in the region by about midnight tonight with
showers lingering after sunset, gradually coming to an end by the
afternoon. Sunday afternoon may actually end up being quite nice
with some sun and clean air due to the rain earlier in the day.
&&
.LONG TERM...
(Sunday night through next Friday)
Issued at 103 PM PDT Sat Mar 29 2025
The cold front from the aforementioned surface low finally moves
through on Monday. However, overall moisture will be limited as
features don`t quite line up favorably for persistent heavy
rainfall. Not to say that there won`t be some pockets of heavy
rain Monday with the frontal passage, but it looks like those
areas will be more limited. When all is said and does Monday
night, rainfall amounts will be around the 0.25-0.5" range for
most with higher amounts up to 1-1.5" in the coastal ranges and
northern Sonoma/Napa.
Numerical guidance has finally trended in the right direction when
it comes to exhibiting confidence in the forecast. There are still
a few outliers on the high end of rainfall through the middle of
the week, but overall models have trended much drier through the
rest of the period, favoring a dry northwest flow regime. At this
point we are looking at some scattered showers Tuesday morning as
the rest of the surface low moves through. Totals are likely to be
on the order of a tenth of an inch or two, with some locations who
are lucky to see the heavier showers getting up to a half inch.
These locations most likely in the North Bay. At this point I`d
call it a medium confidence forecast, solely based on the behavior
of guidance over the last couple of days. However, a rather notable
increase in confidence over this time yesterday. For the latter
half of the week into next weekend, it looks like we`ll be on the
drier side with hints of more spring-like weather...potential for
temps in the 60s to 70s next weekend.
&&
.AVIATION...
(06Z TAFS)
Issued at 809 PM PDT Sat Mar 29 2025
A warm front will quickly move eastward reaching the Bay Area
Sunday morning. Lower cloud ceilings, rain and gusty southerly
winds will develop late tonight and Sunday morning. Low level wind
shear will occur for a few hours prior to the arrival of the warm
front Sunday morning. The RAP model for example shows 30-40 knots
of lower level southerly winds 12z to 15z Sunday morning at SFO
Airport. Once the front passes to the east, showers will linger in
the afternoon and evening.
Vicinity of SFO...Moderate to high confidence VFR persists through
the evening. Ceilings lowering and rain developing with the approaching
warm front by early Sunday morning. Rain and strong and gusty south
to southeast wind 25 to 35 knots 15z to 22z Sunday, wind diminishing
in the mid to late afternoon.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Moderate to high confidence VFR persists
through the evening. Ceilings lowering and rain developing by early
Sunday morning. Strong and gusty southeast winds upwards to 30 knots
at the terminals, possibly higher to 40 knots at Salinas Airport
Sunday.
&&
.MARINE...
(Tonight through next Friday)
Issued at 809 PM PDT Sat Mar 29 2025
Strong southerly winds are forecast across the coastal waters on
Sunday with gusts up to gale force. Moderate to occasionally rough
seas are also expected through early next week. Rough to very
rough seas return Tuesday as a low pressure system brings a strong
northwest breeze to the coastal waters through mid week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 3 PM PDT Sunday for Mry Bay-SF
Bay N of Bay Bridge.
Small Craft Advisory until 3 AM PDT Sunday for Pt Arena to Pt
Reyes 0-10 nm.
Gale Warning from 3 AM to 9 AM PDT Sunday for Pt Arena to Pt
Reyes 0-10 nm.
Gale Warning from 3 AM to 3 PM PDT Sunday for Pigeon Pt to Pt
Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt
Reyes to Pigeon Pt 0-10 nm.
Gale Warning until 9 AM PDT Sunday for Pt Arena to Pt Reyes 10-
60 NM.
Small Craft Advisory until 3 PM PDT Sunday for Pigeon Pt to Pt
Pinos 10-60 NM.
&&
$$
UPDATE...Canepa
SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Canepa
MARINE...Canepa
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Area Forecast Discussion
National Weather Service Omaha/Valley NE
1051 PM CDT Sat Mar 29 2025
.KEY MESSAGES...
- Showers and thunderstorms (60-90% chance) continue this
afternoon into the evening hours. A marginal risk of severe
weather exists across southeast Nebraska and western Iowa.
- Severe threat diminishes late this evening, with showers
continuing into the overnight hours (20-40% chance). A
changeover to snow will occur across northern portions of the
forecast area late tonight through early Sunday morning. Snow
accumulations will be light at less than a 1/2 inch.
- Showers exit the area late Sunday afternoon, with pleasant conditions
expected for Monday.
- Next round of precipitation will impact the area Tuesday and Wednesday
(60-90% chance), with rain, strong storms, and a rain/snow
mix.
&&
.DISCUSSION...
Issued at 336 PM CDT Sat Mar 29 2025
.SHORT TERM.../Today through Sunday Night/
Our active weather pattern continues today as a low approaches the
area. 20z RAP upper air objective analysis shows the closed 850 mb
low across central Nebraska, with much of southeast Nebraska and
southwest Iowa within the warm sector of the low. As this low
continues moving eastward, expect low to mid level QG forcing to be
on the rise. This will lead to the gradual increase of rain showers
and thunderstorms as we head into the afternoon and evening hours.
KOAX radar is already picking up on a few showery echoes, mainly
along and north of the I-80 corridor. Did decide to lower high
temperatures today from NBM guidance, given that with the resultant
cloud cover and shower/thunderstorm activity, highs will struggle to
get above the low 70s across the far southern portions of our
service area.
By the late afternoon and evening hours, we will see a strengthening
LLJ within the warm sector of the low. This will result in a
reinforcing shot of Gulf moisture evident from RAP and HRRR 1000-
850mb moisture transport. BUFKIT soundings across southeast Nebraska
and southwest Iowa continue to indicate that instability will be
elevated here. A few exceptions should be noted, however,
particularly along the Nebraska/Kansas border where possibly some
surface based instability could occur, but this will be highly
dependent on how much CIN can be eroded from an elevated warm layer
between 700 and 800 mb. Regardless, anywhere from 500 to 1500 J/kg
of MUCAPE is seen generally along and south of I-80, with higher
instability values farther south into Kansas and Missouri. This
instability coupled with 0-6 km bulk shear values of 35-45 kts seen
from CAMs indicate that severe potential (including some supercells)
exists along the aforementioned I-80 corridor and areas south,
and this matches well with the marginal risk of severe weather
that the Storm Prediction Center has issued for this afternoon
and evening. The main threats from these storms will be large
hail (with the height of the wet bulb zero anywhere from 8,000
to 10,000 ft) and strong winds. Soundings reveal a pocket of dry
air anywhere from 700 to 400 mb, resulting in DCAPE values of
800-1000 J/kg within the marginal risk area, which adds
confidence to the strong wind risk. A brief spin up is not out
of the question either late this afternoon into the early
evening hours as hodographs show some low level turning,
particularly near the triple point, leading to the slight
clipping of the 2% SPC tornado risk.
Slight variations in low placement and convective initiation
continue to be seen in some of the most recent CAM guidance. Latest
18z HRRR run shows initiation within the warm sector of the low
around 22z across far southwest Iowa associated with the warm air
advection push, with cells quickly moving into the DMX forecast
area. A secondary round of cells develop around the 1-2z timeframe
along the cold front across far southeast Nebraska and quickly race
northeastward into portions of Missouri and Iowa. Other CAMs like
the NAM Nest and ARW show initiation well east into central Iowa by
the 0-1z timeframe, while the FV3 seems to somewhat mirror what the
HRRR has. Regardless of whichever scenario plays out this evening,
we will continue to monitor trends and the latest guidance. Make
sure to stay tuned to the forecast for the latest updates regarding
potential watches or warnings.
The severe potential will gradually diminish as we head into the
late evening hours tonight with storms pushing east. However,
scattered rain showers will continue late tonight through the
morning hours Sunday (20-40% chance) as they wrap around the sfc
low. A changeover from rain to snow will occur across our far
northern counties late tonight as temperatures will cool to the low
30s there, while the rest of the forecast area should see rain.
Snowfall accumulations will remain very light at less than a half
inch across Knox County. Any remaining snow/rain showers will end by
Sunday afternoon as the sfc low continues to push east toward the
Great Lakes area. Highs Sunday will warm to the 40s areawide.
.LONG TERM.../Monday through Thursday/
Pleasant weather conditions return for Monday as a sfc ridge from
the Saskatchewan/Manitoba area dips southward into the Northern
Plains. This will lead to light winds and partly cloudy skies with
some peaks of sun as highs reach the mid 40s to mid 50s. Make sure
to enjoy this brief period of quiet weather, as Tuesday and
Wednesday look to be fairly active. By late Monday night, a
shortwave will deepen and eject from the Rockies area. This will
induce lee sfc cyclogenesis, with QG forcing again overspreading the
area by early Tuesday morning leading to widespread PoPs. Similar to
the last forecast package, the NBM continues to hint at a rain/snow
mix early Tuesday morning across our far north, with rain expected
elsewhere. Thunderstorms may form by the evening hours Tuesday as
instability returns to the area. Some of these storms could be
strong to severe, with portions of eastern Nebraska and western into
central Iowa outlooked for severe weather as seen from the Storm
Prediction Center`s day 4-8 outlook. PoPs will come to an end by
Wednesday evening. However, with this system still several days out,
the track and strength of the low is expected to change, so expect
further refinements/changes to the forecast for those days.
Late in the period models hint at a few shortwaves moving through
which are resulting in the NBM showing some slight PoPs late
Thursday into Friday. Uncertainty exists at this time, however,
regarding timing and placement of these features given differing
model output, so expect this precipitation potential and
placement to change. NBM output has highs for the upcoming week
in the 50s and 60s, with Tuesday and Wednesday being the warmest
days.
&&
.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1051 PM CDT Sat Mar 29 2025
IFR to occasional MVFR ceilings expected to remain in place
overnight with some patchy drizzle and showers and times, most
likely at OMA. In addition, some light snow could approach OFK,
but latest guidance continues to keep the higher chances to the
north. Ceilings should start to approach 1500-2000 ft agl by
late morning/early afternoon and continue to gradually rise in
the evening. Otherwise, winds will remain northwesterly with
gusts of 20 to 25 kts through much of the period.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&
$$
DISCUSSION...Castillo
AVIATION...CA
Area Forecast Discussion
National Weather Service Pocatello ID
554 PM MDT Sat Mar 29 2025
.KEY MESSAGES...
- Rain and snow showers will slowly diminish this evening,
continuing through Sunday morning in the mountains east of
I-15 to the Wyoming border. Overall impacts will be very
limited.
- A brief ridge of high pressure on Sunday will bring a return
to mostly dry conditions across the Snake River Plain as
localized snow showers continue in some mountain areas.
- Daily precipitation chances will increase for early next week
as a series of Pacific systems support a mix of rain/snow
showers and near normal to below normal temperatures.
&&
.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 117 PM MDT Sat Mar 29 2025
Satellite imagery shows weakly closed low spinning through Idaho
early this afternoon. Mix of clouds and sun have allowed for a
few showers to develop ahead of the low, and a few thunderstorms
will still be possible this afternoon in area of best
instability north of the low. Snow levels have risen slightly
with the warmer temperatures of the day, rising to 6000-6500 ft
ahead of the trough axis associated with the low, and 5500-6000
ft behind it this afternoon. Lower elevations should see rain,
and though most of the Snake Plain should be the driest of East
Idaho, can`t really rule out a shower anywhere today. Snow
levels fall back to valley floors overnight tonight with low
temperatures back to or just below freezing. Wrap around
moisture lingers across the central mountains and along the
Divide overnight, while the trough still lingers along the
eastern highlands. There is still a very low confidence chance
of light snows from the wrap around moisture making it into the
northern portions of the Snake Plain, with the NAM Nest bringing
a very hint of light precip as far south as the Mud Lake area.
The latest runs of the other high-res models have remained dry
that far south, so have left out for now, but this may be an
impact to watch for going forward into tonight. Snow totals
remain light, maxing out roughly 3-5" higher elevations along
the Montana border.
Sunday starts out dry for most areas, but weak shortwave ejects
northeast across Idaho very late in the day. There should be
enough sunshine available during the afternoon, that afternoon
build-ups over the snowpack could drop a weak shower across
higher terrain. Not a surprise that the NBM developed barely-
there 15% PoPs across higher terrain this time of year ahead of
this shortwave feature for Sunday afternoon. Better PoP and more
organized QPF develop during the evening and overnight across
East Idaho leading into early next week. Temperatures warm up
for overnight lows, so rain would be expected at most lower
elevations.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 117 PM MDT Sat Mar 29 2025
The extended forecast remain an active one as we wrap up March and
head into April. Monday will still be a "warmer" day with highs in
the low 50s in the eastern Magic Valley and Snake River Plain with
precipitation chances making their return early Monday morning as
the first wave of energy is ejected from a low sitting off the coast
of the PNW moves through our area. With temperatures well above
freezing on Monday and falling to very near freezing by Tuesday
morning, very little to no snow accumulation is expected down in the
eastern Magic Valley and Snake River Plain and any snow that does
fall in the upper Snake River Plain would mostly likely stay below
an inch. As you would venture to guess, snow totals will be
increasing as you go up in elevation with the NBM showing about a 20
to 30 percent chance of at least 6 inches of snow at Galena Summit,
a 50 to 60 percent chance of at least 6 inches of snow in the Island
Park area, and a 50 to 60 percent chance of at least 8 inches of
snow at Emigration Summit in the 48 hours from Monday to Wednesday
morning. The cold front that comes through on Monday will bring
afternoon highs back down into the 40s for Tuesday, Wednesday, and
Thursday. Look for wind gusts to increase on Tuesday, too, into the
35 to 40 mph range in the eastern Magic Valley and lower Snake River
Plain. We will see a brief lull in the activity on Wednesday, but
then the next system moves right into for the second half of the
week, so the overall active pattern continues. Models are showing a
pretty solid blocking pattern setting up over the West next weekend
to give us a break from the precipitation, but we will have to see
how the forecast holds between now and then.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 554 PM MDT Sat Mar 29 2025
The "most-likely" scenario for aviation across southeast Idaho is
low-impact, VFR conditions over the next 24-36 hours...but with some
messiness and perhaps brief exceptions. Trends for the evening into
the first part of the overnight will generally be diminishing
showers, very slowly decreasing winds, and cloud cover trending
toward SCT. We largely focused on refining timing on end of VCSH and
stepping the winds down in the 00z TAFs just issued. Could still see
a brief period of -SN at KDIJ sometime between 04z/10pm and 09z/3am
per a couple of the CAMs, so kept the TEMPO going there. The HREF
does support a fairly moist low-level airmass tonight with good
coverage of RH values over 90%, and both the HRRR and NBM are
responding with some combination of low stratus and/or BR/fog, but
it`s a really messy setup. A break in high-level clouds for the
first half of the night may allow for a period of better radiational
cooling, but another shield of SCT to BKN high-level clouds is
forecast to arrive from the Pacific by early morning, which would
tend to favor stratus over fog and may even keep any stratus
development a bit higher off the sfc. Meanwhile, both the HRRR and
NBM focus best fog/stratus potential out over the Snake Plain and
Shoshone Lava Beds NE to the Arco Desert, keeping KBYI, KPIH, and
KIDA right on the edge. And, a trend toward breaking any development
up is noted early to mid-morning Sunday...perhaps in response to the
advancing high-level cloud shield. Also meanwhile, MOS guidance
shows no hits to cigs/vsbys anywhere, and sfc winds stay a bit
elevated for a good portion of the night at KPIH and KIDA which
isn`t favorable for fog. All things considered...we have no
confidence on how this will play out. Went ahead and hinted at a
period of lower clouds (FEW015) at KBYI/KPIH/KIDA roughly timed out
with NBM/HRRR guidance for start times, and just let it ride until
afternoon wind/VCSH FM groups kick in Sunday. Sunday in some
respects should broadly serve as a break between systems, but there
is just enough moisture/instability that we are carrying some
generous VCSH Sunday afternoon. Overall forecast confidence is high
in low-impact, VFR conditions at the TAF terminals after about 16-
17z/10-11am Sunday, and winds regionwide look lighter Sunday
afternoon with just the normal diurnal pattern at KSUN (no
crosswinds). Looking ahead, Monday will feature a return of more
widespread rain/snow, and lower cigs, as a more substantial low
pressure system moves into the region.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...DMH
LONG TERM...AMM
AVIATION...KSmith
Area Forecast Discussion
National Weather Service Shreveport LA
940 PM CDT Sat Mar 29 2025
...New UPDATE...
.UPDATE...
Issued at 923 PM CDT Sat Mar 29 2025
Precipitation has dissipated and/or exited to our east this
evening and that should stay the case until later tonight when we
begin looking upstream for strong to severe convection that will
move east of the I-35 Corridor, eventually moving into the I-30
Corridor of NE TX, SE OK and SW AR. Latest run of the HRRR
suggests that some of these storms could remain severe as they
move into the northern half of NE TX and/or SE OK so have expanded
overnight pops slightly across our NW half and given the fact
that SPC has upgraded their DayOne Convective Risk across this
same general area. Have added the possibility of Severe
Thunderstorm Wording to the weather type for our overnight hours.
Given the steep lapse rates that will be moving across this
general area overnight, hail appears to be the main threat but a
wind threat could materialize the closer we get to sunrise in the
morning as well.
Hourly temperatures are in the ballpark so did not make any
changes to the temperature forecast for the remainder of the
night.
13
&&
.SHORT TERM...
(This evening through Sunday Night)
Issued at 229 PM CDT Sat Mar 29 2025
The upper-level disturbance responsible for the recent rain
continues to push east into the Lower Mississippi Valley. Some
widely scattered showers and isolated thunderstorms continue to
develop and push northward across our Louisiana and South-Central
Arkansas zones, generally east of the Interstate 49 corridor. In
wake of this precip, we will see some glimpse of the sun move in
across the region from west to east. Eventually, all the precip
should move out of the region by sunset.
However, the dry weather will be short-lived, as showers and
thunderstorms will return to the region on Sunday ahead of an
approaching cool front. In fact, short-term progs have some
isolated thunderstorms returning as early as the pre-dawn hours,
with the bulk of this activity generally expected to be across
East Texas, Extreme Southeast Oklahoma, and adjacent Southwest
Arkansas west of the I-49 corridor. It isn`t out the question to
see a couple strong to severe thunderstorms with this activity.
But, belief is that the AM convection will be short-lived and
will diminish just after sunrise. Southerly winds will be on the
increase on Sunday, but should stay below the sustained 20 mph
Wind Advisory threshold. In response to the winds, expect an
increase in low-level moisture and above normal temperatures.
Highs will top out in the mid 80s areawide, with dew points
climbing in the mid 60s. This will help create an unstable
atmosphere across the region ahead of the approaching frontal
boundary.
By late Sunday afternoon, models continue to suggest a pre-
frontal trough or dryline like feature will move into the area
ahead of the front, resulting in the development of discrete
storms. With steep mid-level lapse rates and decent effective
bulk shear, all modes of severe weather will be possible,
especially large hail and damaging winds. As the front gets
closer, expect a line of storms to form and push across the
region through the pre-dawn hours Monday morning. All modes of
severe weather will remain possible, along with locally heavy
rainfall. /20/
&&
.LONG TERM...
(Monday through next Friday)
Issued at 229 PM CDT Sat Mar 29 2025
Dry weather will return to the region for the first of next week,
but another approaching cold front will bring us a chance for more
severe weather by next Wednesday. At the same time, upper ridging
will build into the southeast CONUS. This will likely stop the
progression of the front and stall it out north of the I-30
corridor through the remainder of next week. Rain chances will
remain across the forecast area during this period, with the best
chances in our northwestern zones. This could also result in
excessive rainfall, with storms expected to train over the same
areas near the frontal boundary. /20/
&&
.AVIATION...
(00Z TAFS)
Issued at 716 PM CDT Sat Mar 29 2025
VFR conditions currently prevailing across all terminal locations
with a dissipating cu field, designated to our eastern terminal
locations only attm. That will change as we move into the
overnight hours with MVFR ceilings developing and advancing
northward through the night. Cannot rule out some brief IFR
ceilings as well, most likely in the vicinity of the LFK terminal.
Introduced VCTS to the TXK/TYR and GGG terminals just prior to
sunrise through mid-morning as decaying thunderstorms will be
possible moving into these areas from N TX. The bigger show will
likely hold off until just beyond this TAF package with scattered
to numerous strong to severe convection on tap for Sunday Evening
into the overnight hours. Look for MVFR/IFR ceilings Sunday
Morning to eventually scatter out and/or become low VFR variety by
late morning into the afternoon hours.
13
&&
.SPOTTER INFORMATION STATEMENT...
Issued at 430 AM CDT Sat Mar 29 2025
Spotter activation will be needed by late Sunday and portions of
the overnight along and ahead of an approaching cold front. /24/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 68 87 61 75 / 10 30 80 10
MLU 67 86 64 76 / 10 10 90 20
DEQ 63 83 48 71 / 50 40 50 10
TXK 67 87 55 73 / 30 30 70 10
ELD 64 86 56 74 / 10 30 80 10
TYR 68 85 57 74 / 40 30 60 10
GGG 66 86 57 74 / 30 30 70 10
LFK 66 85 65 79 / 10 30 50 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
SHORT TERM...20
LONG TERM....20
AVIATION...13