Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/02/20

Area Forecast Discussion...UPDATED

National Weather Service Albuquerque NM

 450 PM MST Sun Mar 1 2020

.AVIATION...
00Z TAF CYCLE
Gusty and erratic winds with virga over northern and western NM will
diminish thru 03Z. This activity will move east to northeast around
25 kt. A weak back door cold front will shift into northeast NM late
tonight with an area of MVFR low cigs developing southward toward
I-40 thru sunrise. Winds will veer around to the south and southwest
by early afternoon across the eastern plains with clearing skies aft
19Z. The next weather system will edge closer to NM from SoCal thru
Monday afternoon with mid level clouds developing once again across
the western half of the state aft 20Z.

Guyer

&&

.PREV DISCUSSION...306 PM MST Sun Mar 1 2020...
.SYNOPSIS...
High temperatures will cool on Monday and there will be a chance of
rain showers, thunderstorms, and high terrain snow showers over
western areas. An upper level low pressure system will pass just
south of NM Tuesday through Wednesday morning with wetting
precipitation and continued cooling mainly south of I-40. The
southeast plains could accumulate up to 1.5 inches of rain, while a
few to several inches of snow will be possible in the south central
mountains including Ruidoso. Dry weather, warming temperatures, and
light winds are expected Wednesday and Thursday, but a back door cold
front should result in some cooling in many areas on Friday.

&&

.DISCUSSION...
SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)...
Mid-level moisture has intruded into western NM this afternoon, with
20-35F dewpoint depressions at the sfc underlying it allowing for
virga to develop. This will expand into the RGV from Socorro to ABQ
to Santa Fe and will produce erratic gusty winds this afternoon.
There is some convective activity apparent on the GOES-16 Day-Cloud-
Phase hinting at mixed phase clouds along the continental divide,
and there could be a stray dry lightning strike as a result. The
virga, along with westerly gusts of 25-40mph mainly through eastern
NM will taper off by or just after sunset as the atmosphere
decouples.

As the virga wanes, wintry weather begins to eek into far northern
NM over the Tusas Mountains tonight. A backdoor frontal boundary
will bring a northerly wind shift into northeastern NM tonight.
Chances for precipitation will remain fairly low, however the HREF
and RAP have been showing another round of virga Monday afternoon.
Under an area of diffluence aloft, there is enough CAPE with -2 to -
4 LI to warrant mention of a chance of thunder Monday afternoon
through western NM. Overall, precipitation accumulations will be
quite paltry with little chance for wetting precipitation. Better
chances for precipitation lay over southeastern NM in the Long Term
Tuesday as this Pacific storm tracks south of NM.

24

LONG TERM...(TUESDAY THROUGH SUNDAY)...
An upper level low pressure system tracking southward along the CA
coast will pass eastward over northern Mexico Tuesday through
Tuesday night, then exit gradually eastward across south TX on
Wednesday. The coverage and intensity of precipitation will
increase over southern areas (along and south of I-40) Tuesday and
Tuesday night, then some lingering precip is expected along and east
of the south central mountains into Wednesday. There may also be
some thunderstorms over southern areas on Tuesday. Rain and liquid
equivalent precipitation amounts should should range from a tenth of
an inch over southwest areas to around 1.5 inches over the southeast
plains. The south central mountains will be favored for snow
accumulation, where a few inches are expected below 7500 feet, and
as much as 10 inches will be possible above 7500 feet. Depending on
how much cold air arrives with a gusty back door cold front on
Tuesday, the Ruidoso area could get more than a few inches of snow.
We will be watching this possibility closely with each new model
run.

In the wake of the upper low, a low amplitude ridge of high pressure
will cross the southwest US Wednesday night through at least Friday
morning with drier and warmer weather. Models are diverging on the
depth and timing of an upper level trough expected to migrate inland
from the west coast Friday. If the latest operational GFS run is
right precip could begin spreading over western areas as early as
Friday, but the NBM ensemble delays spreading precipitation over
western areas until Saturday night and Sunday. Models are in better
agreement on the arrival of a back door cold front early Friday with
a brief downtick in high temperatures that day. Overall the late
weekend trough looks fairly warm with lowland rain showers, perhaps
some thunderstorms, and only high terrain snow on Sunday.

44

&&

.FIRE WEATHER...
The main fire weather concerns may very likely be today with
elevated conditions across eastern NM given warm, dry, and breezy
westerlies this afternoon. Even western NM is seeing a good amount
of virga which will produce some erratic gusty winds this afternoon.
Conditions calm after sunset as the atmosphere decouples. Some non-
wetting precipitation is set to enter into western NM Monday,
shifting toward southern NM Monday night. There will likely be
another round of virga over western NM Monday afternoon producing
erratic gusty winds with a small chance for a stray lightning
strike. The best chances for wetting precipitation will be Tuesday
over southern and southeastern NM as a Pacific storm system tracks
south of the state. Any significant snow accumulations will be
relegated to the high terrain, focusing over the Tusas and
Sacramento Mountains.

Conditions clear out and warm up starting Wednesday through the rest
of the work week. A weak backdoor front looks to swing into eastern
NM Thu, but have little effect on temperatures. Ventilation for the
most part will remain good to very good. MinRH will be low but above
critical each day with good to excellent recoveries. Transport winds
notably shift out of the south Friday as a ridge begins to exit to
the east.

24

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$



Area Forecast Discussion

National Weather Service Bismarck ND

 844 PM CST Sun Mar 1 2020

.UPDATE...
Issued at 843 PM CST Sun Mar 1 2020

Latest fog/stratus imagery loop and surface observations shows
stratus has eroded for most of the west, and not pushing into
central North Dakota. Followed the GFSLamp guidance which has done
a better job in holding onto the stratus verses the HRRR or
RAP13. Should see the stratus continue to dissipate from west to
east and clear the James River Valley by around 06z Monday. High
clouds now over western Saskatchewan associated with warm air
advection will overspread western  and northcentral ND between
09z- 12z Monday, and south central and the James River Valley 12z-
18z Monday. This is out ahead of our next shortwave trough aloft
and surface cold front which slide into central ND Monday
afternoon. Minor changes in this update included holding back more
clouds central this evening, and slowing down the decrease in
winds across the James River Valley for a couple more hours.

UPDATE Issued at 615 PM CST Sun Mar 1 2020

Winds have fallen below sustained and gust wind advisory
criteria, thus have allowed the wind advisory to expire at 6 PM
CST Sunday. Over the next few of hours, expect the stratus to
gradually lift and dissipate as a shortwave ridge approaches and
surface high pressure nudges into western North Dakota from
Montana. Expecting a quiet night ahead with a clearing sky and
decreasing winds this evening.

Otherwise, have issued a flood warning for the Cannonball River at
Breien as the river level is just below minor flood stage, and is
forecast to rise above Minor Flood Stage this evening. This is
expected to be a short duration flood event with the river level
most likely falling below minor flood stage Tuesday afternoon.

&&

.SHORT TERM...(This evening through Monday)
Issued at 322 PM CST Sun Mar 1 2020

Concerns in the short term are the gusty winds for the remainder of
this afternoon and some light rain, and gusty winds Monday.

Current winds are diminishing slowly after this mornings high winds
of 60 to 65 mph moved though with the pressure rise. The winds will
diminish rapidly by evening. Until then we will keep the wind
advisory going.

Otherwise we expect to see some clearing skies tonight, followed by
increasing clouds and Monday as a fast shortwave trough follows and
quickly moves through. At this time we do not think winds will be
nearly a strong as today, but gusty winds of 25 to 35 mph appear
likely Monday afternoon. We expect a few rain showers/snow showers
with this feature.

.LONG TERM...(Monday night through Sunday)
Issued at 322 PM CST Sun Mar 1 2020

The extended period will feature a progressive flow through Thursday
followed by a ridge that should bring mild and dry weather for
Friday and Saturday.

On Tuesday, a strong h300 jet of 135 kts across Montana into
southwest North Dakota should support some light precipitation
across the left front quad, and the ECMWF/GFS support this. This
will end up being some light rain.

Wednesday will see another shortwave trough move through. The GFS
is by far the strongest model with a closed low in Saskatchewan,
but the NAM/ECMWF and SREF remain an open wave. So will follow the
blend which brings a chance for rain and a bit of snow Wednesday
across the north. Otherwise the remainder of the extended looks
mild for Friday and Saturday, then a chance for rain and snow
Sunday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 615 PM CST Sun Mar 1 2020

MVFR cigs begin this taf period at all terminals, however
expecting a return to VFR status by 03z Monday. Gusty northwest
winds to 30kt will also decrease to less than 10kt by 03z Monday
for all terminals except KMOT and KJMS. Wind shear is expected at
all terminals except KJMS between 10z and and 18z Monday. See each
terminal for specific times. Otherwise, another cold frontal
passage is expected after 18z Monday, with westerly winds
increasing and gusting to 35kt.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...KS
SHORT TERM...WAA
LONG TERM...WAA
AVIATION...KS



Area Forecast Discussion

National Weather Service Detroit/Pontiac MI

 657 PM EST Sun Mar 1 2020


.AVIATION...

VFR conditions are in place across Southeast Michigan early this
evening as deep column ridge works across the area. Models show warm
air advection increasing significantly now moving forward. Strong,
unwavering consensus that low level thetae between 2.0 and 5.0 kft
agl will move into Southeast Michigan after 04Z this evening.
Problem is that one has to go back portions of southern Illinois/MO
to get close to some MVFR cigs. Will steady the course and keep
previous timing of MVFR/moisture as model data shows favorable
trajectory to low level jet to maximize moisture advection during
the late evening. Pretty pessimistic on fog tonight given very high
sfc T-Td spreads and the look of RAP soundings. Nevertheless did
keep a light hz mention. Combination of strong low level theta e
advection with cold temperatures aloft will lead to very steep lapse
rates above 500mb late tonight/before daybreak. Liked the signal out
of the HREF probs for a VCTS mention with showers in the 08-11Z
timeframe for the southern taf sites. The shower activity could also
yield some temporary IFR conditions. West flow develops post cold
front Monday morning. Lack of any true cold air advection will mute
the wind response Monday.

For DTW...Prevailing rain showers with VCTS between 08-11Z. Some of
the showers may lead to temporary IFR conditions. Rain clears out
with some modest low level/boundary layer cloud early in the day. No
significant wind expected.

DTW THRESHOLD PROBABILITIES...

* High for ceilings at or below 5000 feet tonight.

* High for precip type being rain.

&&

.PREV DISCUSSION...
Issued at 357 PM EST Sun Mar 1 2020

DISCUSSION...

South wind gusting around 25 mph is proving to be the main driver of
the afternoon temperature response in spite of snow cover and with
modest contribution from sun filtered through high clouds much of
the day. The result is stage 1 of the warming trend consisting of
lower to mid 40s temperatures with a few upper 30s still in the
shandow of Lake Erie and Huron. These readings with dewpoint only in
the teens and 20s is no doubt sublimating some snow cover. NOHRSC
maps already indicate minimal depth in the Saginaw valley while a 2
to 4 inch cover generally extends over the rest of SE Michigan into
northern Indiana and Ohio. This is enough to hang around a while
tonight in stage 2 of the warming trend that consists of a notable
increase in surface dewpoint and boundary layer moisture. Upstream
observations this afternoon indicate lower to mid 50s temperatures
up to Chicago, Muncie, and Dayton. Readings in the mid 60s
accompanied by lower to mid 40s dewpoint reach the Missouri/Illinois
border as of mid afternoon. These readings support expectations of a
rising temperature and dewpoint trend across Lower Michigan after a
muted evening drop tonight. Readings could even push the 50 degree
mark by sunrise Monday.

The low level moisture transport also coincides with the onset of
rain showers that develop late tonight and last through Monday
morning. The activity is supported along and ahead of a weak and
slow-moving cold front that is positioned roughly from Port Huron to
South Bend at sunrise. Model solutions in today`s forecast cycle
look nearly identical to previous runs regarding larger scale
forcing mainly associated with a weak coupled upper jet structure
inducing a surge of fgen in the frontal zone surface to 850 mb. This
is more capable of increased shower intensity and near categorical
coverage south of the I-69 corridor. A rumble of thunder is also
possible near the Ohio border.

The northern stream jet max exits into Quebec and carries the front
south and east of the Michigan border by Monday afternoon. It is
followed by short wave subsidence and dry weather with surface high
pressure lasting through Monday night. A minor intrusion of colder
air is then quickly scoured out as renewed southwest flow develops
during Tuesday. Morning lows in the mid to upper 20s rebound back
into the mid 40s following the passage of a dry but mostly cloudy
trough/warm front.

Westerly low level flow develops Tuesday night and Wednesday on the
south flank of low pressure moving through northern Ontario. Low
level thermal fields and partial thickness indicate minimal
temperature advection during this time which allows generally above
normal conditions to hold through mid week. Precipitation prospects
are dependent on low predictability of a very small scale upper
level impulse that would bring some light rain during Wednesday
afternoon. Extended range models then bring a stronger low into
central Canada by Thursday that has potential to pull another round
of warm air into Lower Michigan on strong SW flow followed by a
longer period of colder NW flow by Friday. Assuming projections hold
on the highly amplified and relatively progressive large scale
pattern, guidance temperatures are then barely down to normal Friday
into Saturday before yet another big warming trend is shown to
finish next weekend.

MARINE...

A fresh to strong south to southeast breeze continues across the
waters this afternoon into the early evening, limited to below 30 kt
by a stable lower atmosphere. Winds will veer to the southwest
tonight as low pressure tracks north of Lake Superior. A cold front
then moves through Monday morning, shifting winds to the west but
without an increase in speed. Winds then remain near or below 10 kt
through the remainder of Monday into Tuesday morning as high
pressure builds in, with the exception being northern Lake Huron
where the gradient will stay a bit stronger, with winds on the order
of 15 to 20 kt there. This high will be short-lived as another weak
low moves across Ontario Tuesday night and brings another weak cold
front through. The rest of the week follows a similar pattern of
alternating high and low pressure advancing through the region with
the better chance for more impactful marine weather holding off
until Friday.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
Lake Huron...NONE.
Lake St Clair...NONE.
Michigan waters of Lake Erie...NONE.
&&

$$

AVIATION.....CB
DISCUSSION...BT
MARINE.......TF


You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.




Area Forecast Discussion

National Weather Service Grand Rapids MI

 1037 PM EST Sun Mar 1 2020

LATEST UPDATE...
Update/Marine

.SYNOPSIS...
Issued at 329 PM EST Sun Mar 1 2020

- An isolated thunderstorm possible near I-94 tonight

- Low clouds and fog tonight

- Possible showers Tue PM

- Another chance for showers/snow shower Thu night into Friday

&&

.UPDATE...
Issued at 1037 PM EST Sun Mar 1 2020

Updated the forecast to remove the mention of thunder in the far
southern forecast area. Instability looks to be pretty meager with
the latest NAM showing 850mb LIs only slightly negative. Deep
layer CAPE is only on the order of a few hundred joules. Just do
not feel this amount of instability is worthy of a mention of
thunder in the forecast. Latest model runs have even tapered back
on the amount of precipitation overall along the I-94 corridor.
Some light fog is possible tonight along and south of I-96, but
not expecting this to be too impactful as visibilities are not
really expected to go below 1-2 miles.

&&

.DISCUSSION...(This evening through next Sunday)
Issued at 329 PM EST Sun Mar 1 2020

-- An isolated thunderstorm possible near I-94 tonight --

Isolated thunderstorms with locally heavy rainfall (over a 1/2
inch in one hour) are more than possible near and south of I-94
tonight. The SPC SREF 3 hour calibrated thunderstorm forecast has
a 5 pct chance of thunderstorms in the 10 pm to 1 am time frame.
As it turns out there is a southern stream shortwave that is being
ejected northeast from the southern plains into northern Ohio
Valley and possibly as far north as the southern Great Lakes. The
1000/805 moisture transport vectors on the RAP model are aimed at
I-94 this evening. This is similar to what the ECMWF shows too.
The HRRR has area of more than .5 inches of 3 hour rainfall near
and south of I-94. Given surface dew point are in the 45 to 50
degree range as close as western Illinois, and precipitable water
values reach near .75 inches this evening, this would make some
sense. In fact the RAP model, for nearly every run of it since at
least 10z has nearly 800 j/kg of MU cape over western Van Buren
county in the 9 pm to 1 am time frame. There is a 40 knot low
level jet helping the cause. The NAM is not as strong on this but
given the continuity of HRRR, RAP and ECMWF and some support from
the GFS, I am thinking showers are likely near and south of I-94.
North of I-94 to much mid level dry air comes in so I do not think
the storms/heavy rain will get north of I-96 tonight.

-- Low clouds and fog tonight --

With all of that moisture being brought north by the frontal
system tonight, and given the snow cover will not be totally gone
in the I-69 area, it makes sense to believe some fog and low
clouds should be expected over the area where snow still remains.
Other locations with no snow on the ground will just see low
clouds with drizzle not out of the question.

-- Possible showers Tue PM --

A stronger northern stream system comes through the area Tuesday
and with it comes a chance for showers in the afternoon and
possibly evening. The GFS and ECMWF have deeper moisture with this
system farther south than does the NAM, given the strength of
this system, I am thing we will see some showers with this. More
than likely it will be rain showers as temperatures will likely be
in the lower 40s in the afternoon Tuesday.

Once the front comes through though we get 850 temperatures
falling near -8c and there is some clouds up to 5000 ft in depth,
so there could be some flurries Wednesday morning.

-- Another chance for showers/snow shower Thu night into Friday --

Overall we still have a progressive upper air pattern with Pacific
shortwaves moving across the CONUS about every 48 hours or so. The
next system impacts this area Thursday into Friday. This looks
to have more impacts on us and more than likely will bring showers
to the entire area ahead of the storm and we get into the deep
cold air aloft behind the system early Friday so I would think
some snow showers are possible.

This is a progressive pattern so it will warm up again over the
weekend and another storm with possible impact is possible by the
middle of next week.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 724 PM EST Sun Mar 1 2020

The main forecast concern the next 24 hours will be some lower
clouds and precipitation that will move into Southern Lower
Michigan tonight. MVFR ceilings are forecast to develop just after
midnight along I-94 and lower to IFR around 200am. This will
coincide with some precipitation that will be moving through.
Visibilities will likely dip to IFR levels as well in some fog and
rain. The I-96 TAF sites will largely be spared, but some MVFR
conditions are expected for a time after 100am. The rain should
remain off to the south however towards I-94. The low clouds will
move out to the east through the course of Monday morning. By
noon, VFR conditions should prevail.

In regard to wind a cold front will pass through the area tonight.
South winds will turn to the west tonight and the northwest on
Monday. There may be a few hours of low level wind shear this
evening where 2000ft winds are southwest around 45 knots through
03z.

&&

.MARINE...
Issued at 1037 PM EST Sun Mar 1 2020

We will let the Small Craft Advisory expire at the top of the
hour. Latest model runs of the WaveWatch3 and the GLERL model both
show wave dropping below 4 feet. Winds have fallen to below 15
knots at Big Sable Point. Winds and waves should stay below SCA
criteria through Monday night.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Small Craft Advisory until 11 PM EST this evening for LMZ844>849.

&&

$$

UPDATE...Duke
SYNOPSIS...WDM
DISCUSSION...WDM
AVIATION...Duke
MARINE...Duke




Area Forecast Discussion

National Weather Service Chicago/Romeoville, IL

 848 PM CST Sun Mar 1 2020

.UPDATE...
846 PM CST

Main update this evening was to tighten up the PoP gradient on
the northwestern flanks and to generally reduce thunder chances to
a narrower corridor across our far southeastern counties
overnight.

Mid-evening moisture channel imagery reveals our initiating
shortwave in question translating fairly swiftly across central
Missouri. Based on its current more easterly translation
component, it appears most of the large-scale DCVA-induced forcing
for ascent will remain confined mainly to our far south and
eastern counties overnight. Noting developing elevated showers off
to our southwest at the edge of the main mid-level moisture
plume, and this spotty activity should continue to develop
northeastward through the evening hours, although this may
initially struggle as it moves into a drier airmass. At the surface,
a cold front is just about to move through the Rockford area and
will continue to push through the forecast area overnight. This
intrusion of cooler/drier air will set a northwestern terminus to
any potential shower or embedded thunderstorm activity that will
be continually marching southeastward with time.

Surface observations show the 50 degree isodrosotherm is still
well off to our south, closer to the I-64 corridor across southern
Illinois, which is notably farther south than midday model
guidance (RAP/HRRR) would have suggested. Recent VAPOR AMDAR
soundings out of Midway reveal that things are pretty parched
through the low and mid-levels, and even ILX`s evening RAOB
sampled plentiful lingering dry air below 600 mb. So, while mid-
level lapse rates are more than supportive of thunderstorm
development, pretty marginal moisture and thermodynamic profiles
look to chew into this potential a good deal tonight.

With this in mind, have confined the thunder mention for the rest
of the overnight to areas south of a Pontiac to Valparaiso line
and also trimmed PoPs in the vicinity of I-55 as the incoming
front looks to scour moisture out before the main slug of mid-
level moisture arrives. Should still see some pretty good shower
coverage east of I-57 tonight before everything shifts east of our
area by daybreak on Monday. Updated products have been sent.

Carlaw

&&

.SHORT TERM...
135 PM CST

Through Monday night...

A significant but somewhat short lived air mass change continues
this afternoon as dewpoints climb into upper 30s and the 40s are
knocking on the door. Several features of note on water vapor
pictures, a strong jet core across the southern tier of states,
with a few smaller scale disturbances in mostly westerly flow
aloft to our south, maybe a slightly more distinguishable wave
moving into MO early this afternoon.

Morning soundings out of Little Rock, AR and Springfield, MO depict
the airmass that will advect toward the area ahead of an approaching
cold front this evening. A noted but modest increase in PWATs up to
0.55" but with impressive lapse rates in excess of 8 deg/km around
the 700-500 mb layer, and quite the elevated mixed layer a bit
further upstream at Fort Worth, TX and PWATs in excess of 0.75". RAP
modeled soundings are a tad moist at this point.

The driver for the cold is a more significant upper low across the
northern international border region. This will drive through the
upper Great Lakes tonight and push the cold front into the area this
evening and through the area by Monday morning. This aforementioned
features will lead to an expansion of showers and thunderstorm
across the mid Mississippi valley late this afternoon. The cold
front will provide for a sharp cut off in the precip axis which
still roughly aligns with the I-55 corridor. The better moisture
will certainly shift into the Ohio Valley thus some mixed signals
on the strength of the precip and instability this far north, but
enough moisture will advect to our area to support a period of
some decent showers. Cannot argue against the chance of a few
thunderstorms given the impressive lapse rates upstream, and
narrow ribbon of moisture ahead of the front,  with a little
better signal south of I-80 across east central IL and into
central IN. Main time window is 9PM CST until about 2-3AM CST.

The cold front will quickly move through overnight ending precip
chances. Northwest flow will maintain a cold advection regime on
Monday, with highs back more in the department of normal or slightly
above under mixed sun and clouds. Noted the previous AFD mention of
lake breeze potential which should form. Current 12z runs depict
925-950 mb flow would be strong enough to keep it at bay for most
of the day before the flow weakens at a diurnally unfavored time
for a lake breeze to move inland too much, but this will be more
of a mesoscale feature to see how the hi-res models resolve
tomorrow.

High pressure will shift through the lower Great Lakes region Monday
night supporting cool temperatures and fog would be possible in some
areas, with some hints that this may be favored across the recently
rained areas of EC IL and NW IN, though there is enough low level
flow to suggest it would shallow.

KMD

&&

.LONG TERM...
125 PM CST

Tuesday through Sunday...

A split flow regime will remain in place mid week with a strong jet
across the Ohio Valley ahead of a southwest trough and the northern
stream pushing out of the Canadian northwest/Rockies. The southern
jet should keep the better moisture south of the Great Lakes with
our weather potentially more influenced by the northern stream.
The surface low associated with the shortwave trough in the
northern stream will pass well north of our area, which should
keep precip limited with the first wave Tuesday morning, but a
weak cold front will nevertheless slide through Tuesday night
accompanied by a sharper upper trough. After a day of mixing and
the cut-off low preventing any northward transport of meaningful
moisture, The front will likely come through dry.

Wednesday will be breezy with northwest winds in the wake of the
cold front and with the front of Pacific origin we will likely only
see a smaller dip in temperatures, though it may feel cooler with
the northwest breezes. Winds will quickly become southwesterly again
by Thursday in advance of the next shortwave trough, which will help
boost temperatures toward the upper 50s.

The second cold more potent front of the week will sweep through
Thursday evening. Model guidance does paint some light QPF with this
stronger front, though moisture is still limited and this front
may yet still some through dry in with the cut-off low still
meandering along the Gulf hogging moisture. A pocket of colder air
will be found behind the front this time around, Friday will end
up the coolest day this week with highs in the 40s, still near or
maybe a tad above normal, though it will be breezy again to make
it feel cooler, especially lakeside. There are some lakeshore
flooding concerns in Northwest and portions of Cook County given
the gusty winds behind this stronger front.

The weekend will begin dry and mild as upstream ridging and deep
south-southwest flow returns (some cooling IL lakeside due to some
SE component possible), but there are some inconsistencies in model
guidance as to if the ridge will hold precip off through the whole
weekend, but conditions will remain on the mild side.

KMD

&&

.AVIATION...
For the 00Z TAFs...

A cold front will shift southeast across the area late this evening
into the early overnight hours. Observational data and model
guidance has suggested a southward trend with associated SHRA and
embedded TS that is expected to develop along the front late this
evening. While ORD/DPA/RFD were already expected to remain dry, the
southward shift will likely keep MDW dry as well and push the TS
chance south of GYY. However, an isolated light shower cannot be
ruled out for MDW around midnight, while scattered showers are
expected around the same time for GYY.

The southward trend in precip has also resulted in a trend to higher
ceilings for all Chicago metro sites, with VFR ceilings now expected
at all sites but GYY through the period.

SW winds around 10 knots ahead of the front will become NW 10-15
knots, with some gusts nearing 20 knots possible at times on
Monday.

Kluber

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&

$$

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Area Forecast Discussion

National Weather Service Pueblo CO

 331 PM MST Sun Mar 1 2020

.SHORT TERM...(This evening through Monday)
Issued at 331 PM MST Sun Mar 1 2020

Main forecast concerns/challenges are with the expected winter
weather this evening into Monday morning, with periods of heavy snow
likely causing hazardous travel during the overnight hours and
Monday morning commute.

In the near term, outside of the higher elevations, mainly dry
conditions still in place across much of the area. Radar imagery
depicting some light returns over southeast Colorado, however, this
is currently stemming from mid/high clouds with no precip likely
making it to the surface. Do expect that to change over the next
several hours though as large scale ascent further increases.
Previous wintry precip trends with model guidance has continued with
today`s guidance, with snow increasing across the higher elevations
late this afternoon and a rain snow mix likely developing over
adjacent locations. Still anticipate mid/upper level flow to
increase while several short wave troughs noted on latest satellite
imagery traverse this flow. Meanwhile, surface front in place across
Colorado surges southward this evening, with northerly winds and
gusts strengthening into the night. Should then see precip really
develop and spill into Teller and El Paso counties by early to mid
evening. A rain snow mix may initially occur, but think stronger CAA
post FROPA and increasing forcing will quickly cool the column, with
thermal profiles then likely supporting all snow by mid evening.

Previous concerns of a window of more focused and heavy snow remain
and have even increased, especially along the I-25 corridor from mid
evening to early Monday morning. Not only is upslope flow focused in
this location that would bring bands of snow across the Palmer
divide, but most guidance indicating a fairly long window of more
focused isentropic ascent in this location. This would support
additional banded heavy snow. Additionally, the anticipated CAA will
likely help keep already steep low and mid level lapse rates in
place, per latest RAP analysis. This would all then produce a period
of stronger snow development into early Monday morning. While
current forecast snow amounts of 3-5 inches are expected across
northern El Paso county, do think locations across southern El Paso
county back southwest to around Canon City could see these amounts.
Also, the banded nature of this snow will likely produce highly
variable amounts, and even locally higher amounts. So will continue
to closely monitor trends and latest guidance, to hopefully pin
point where exactly this may occur later tonight.

So, with the expected heavy snow and high snowfall rates, snow
covered and slippery roads, and significantly reduced vis all
producing hazardous driving conditions overnight tonight and for the
Monday morning commute, felt an Advisory was warranted. Did even add
parts of Fremont county as this looks to be in this favored
location. Pueblo county will need to be monitored for possible
inclusion in this Advisory, as they will be right on the line of
this potential heavier snow. At this time, most of this looks to
stay just to the northwest and west, however, it`s still possible
for a heavy band to develop overhead. Another aspect to monitor for
Pueblo will be with the rain snow mix and then transition to all
snow tonight. A mix of rain and snow before cooling conditions
tonight, may support more icy road conditions. Confidence is not
high on this potential though at this time.

Expect snow to likely continue across the higher elevations Monday
morning, but likely come to an end over the plains. Did add a small
window of patchy freezing drizzle/rain to the forecast for a time
Monday morning though. Guidance showing rather moist lower levels
lingering Monday morning, and with some light upslope flow still in
place, do think it`s a possibility.

.LONG TERM...(Monday night through Sunday)
Issued at 331 PM MST Sun Mar 1 2020

Monday Night and Tuesday:

As advertised in previous forecasts, the upper level low pressure
center will propagate west to east over Mexico and through Texas. No
major impacts are expected due to how far south the low pressure
system is. Very pleasant weather is expected Monday night and
Tuesday. There isn`t much expected for cloud cover, the winds will
be relatively lights, and the temperatures will be right around
average for this time of year. Enjoy!

Wednesday through Sunday:

A warming trend will begin as an upper level ridge develops over
southern Colorado, with the warmest day expected to be Saturday and
temperatures expected to be around 10 to 20 degrees F above average.
Each day will have critical or near critical fire weather conditions
over the plains. Wednesday, Friday, and Saturday seem to be the days
with better fire weather conditions as they are associated with the
best downslope flow off of the eastern mountains. Otherwise, dry
conditions are expected through Saturday morning. Long term models
are resolving the next low pressure system impacting southern
Colorado by Saturday morning. There is still a lot of uncertainty
with timing, but the impact are expected to bring snow only over the
mountains.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 331 PM MST Sun Mar 1 2020

KALS:

VFR conditions are expected for KALS throughout the forecast period,
but there will be vicinity rain and snow showers during the
overnight. If a rain or snow shower develops over the forecast
point, MVFR to IFR conditions are possible. Otherwise, morning and
day are expected to be VFR.

KCOS and KPUB:

A cold front is expected to develop over KCOS and KPUB this evening
which will bring snow, heavy at times to both locations. Expect
conditions ranging from MVFR to LIFR during the overnight and
morning. Low level saturation and weak upslope event will keep fog
over KCOS and KPUB through the morning, so MVFR to IFR conditions
are expected. During the late morning to early afternoon, fog is
expected to mix out and VFR conditions will return.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 7 AM MST Monday for COZ077-081>085.

&&

$$

SHORT TERM...RODRIGUEZ
LONG TERM...SKELLY
AVIATION...SKELLY




Area Forecast Discussion

National Weather Service Springfield MO

 532 PM CST Sun Mar 1 2020

.SHORT TERM...(This evening through Tonight)

It felt like a spring day over extreme southeast Kansas and the
Missouri Ozarks. Breezy south winds brought in a Gulf airmass,
which will set the stage for showers and thunderstorms this
evening and through the overnight hours.

A few of these storms could become strong to severe, with large
hail up to the size of quarters being the primary risk. There will
also be a very limited risk for a damaging wind gust or two. Deep
layer shear will be the limiting factor, as 0-6km values only
range from 20 to 30 knots. Models have increased CAPE progs
ranging from 1000 to 1500.

There will also be a flash flood risk along a narrow corridor.
This corridor will likely stretch roughly from Columbus Kansas to
Springfield, and then east along the Highway 60 corridor. The HRRR
and RAP have consistent signals with each other, and have
consistently showed this potential each hourly run today. This
zone is correlated with an 850mb jetlet that triggers convection
around the Joplin/Columbus Kansas area around 9 or 10pm this
evening.

Showers and thunderstorms will likely shift south and east of the
CWA by early Monday morning.

A Flash Flood Watch for tonight is being considered for a narrow
corridor from Columbus Kansas eastward along the Highway 60
corridor.

.LONG TERM...(Monday through Sunday)

Northwest flow will push the frontal boundary into Arkansas by
early Monday, setting the stage for several days of dry and mild
weather.

The Ozarks will remain under the influence of northern stream
energy as the southern belt churns across the deep south within
the split flow regime and tropical atmospheric river.

Locations across the I-20 and I-40 corridors will rob any low
level moisture return to the Ozarks as widespread convection
occurs in this area through Thursday morning.

Another shot of continental air will spread across the region
early Friday morning. This front will be rain free given the dry
air in place.

A large upper ridge of high pressure builds across the nations
midsection for next weekend. This feature will help boost
temperatures back into the 60s, and possibly the 70s by Sunday
afternoon. No rainfall is expected through Saturday night.

A precipitation signal then occur by late Sunday which could
feature some heavy rain given the upper pattern and stationary
southwest to northeast baroclinic zone.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 529 PM CST Sun Mar 1 2020

A weak cold front will move south through the region this evening
into the overnight hours. Scattered showers and a few storms are
expected to develop along the front. Due to limited coverage
confidence was too low to include a mention of thunder at this
time in the TAFs, did include a TEMPO group for showers in the
TAFs as coverage in showers should be greater than thunderstorms.
If the TAF sites are affected by thunder it will be in the same
time range as they would be affected by showers. Will amend the
TAFs as needed this evening if confidence in a TAF site being
affect by a thunderstorm increases.

Ceilings will lower into the MVFR range and possibly the IFR
range behind the front. Winds will also switch to the north after
the frontal passage.

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

SHORT TERM...Cramer
LONG TERM...Cramer
AVIATION...Wise