Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/03/19
Area Forecast Discussion
National Weather Service Denver/Boulder CO
737 PM MST Sat Mar 2 2019
.UPDATE...
Issued at 737 PM MST Sat Mar 2 2019
Widespread snow will continue through the evening and then
decrease after midnight. Several bands of heavy snow are lightning
up the radar. Snowfall rates are likely an inch or high under the
bands of heavy snow. Going forecast is on track with only minor
changes made. Cold air continues to pour into northeast Colorado
overnight with wind chill values falling to -10 to -20. Will
mention these in the Winter Weather Advisory statements. For
Sunday, cloudy and cold conditions will prevail. Areas of snow
continue in the mountains, while light snow/flurries will be
possible east of the mountains.
&&
.SHORT TERM...(This evening through Sunday)
Issued at 318 PM MST Sat Mar 2 2019
Radar data shows coverage of snowfall beginning to increase up and
down the I-25 urban corridor as moisture aloft continues to
increase. Satellite imagery shows solid cloud cover all the way
back to central Nevada as the surge of Pacific moisture continues
its eastward track. HRRR models have been indicating that
precipitation would be increasing after about 3 PM. This should
lead to several hours snowfall across the forecast area this
evening. At the surface, cold air has been moving down from the
Cheyenne ridge with temperatures in northern Weld County now in
the upper single digits. Cold air will also be coming in from an
easterly and northeasterly direction overnight. Low level upslope,
abundant moisture aloft and upper level jet dynamics will all
combine to spread light to moderate snow across the forecast area.
Mountain areas have been receiving light to moderate snow all
afternoon, which should continue. Indications from the HRRR and
RAP models are that the primary band of snow over northeast
Colorado will be over the Denver Metro area and Palmer Divide.
These areas will probably see something like 4 to 6 inches of snow
overnight. Most of the snow should fall by midnight with a
decrease in intensity after that. The current list of Winter
Storm Warnings and Winter Weather Advisories are in agreement with
the latest thinking, so no changes will be made at this time.
On Sunday, the central mountains may continue to see light to
moderate snowfall while locations further to the north will only
see light snow showers. On the plains, the entrenched cold airmass
will support snow flurries and some light snow showers, but not
much additional accumulation. High temperatures will only be in
the mid teens.
.LONG TERM...(Sunday night through Saturday)
Issued at 318 PM MST Sat Mar 2 2019
An active pattern continues in the long term, but with a general
warm up through the period.
An upper jet maximum will push over the state with the right
entrance region to pass over the forecast area Sunday night. Most
models place the area where banding will likely occur over and
along the I-70 corridor, from the mountains down onto the plains.
This band will likely put down 2 to 5 inches over the mountains
and another 1 to 2 inches over the plains. This will be covered by
the Winter Storm Warning for the mountains around I-70, to cover
the bad driving conditions for the end of the weekend back from
the mountains. Won`t issue anything for the plains at this point,
as it`s hard to pinpoint the band location. As the whole system
sinks south, cold arctic air will continue to filter in from the
north, and with partially clearing skies, the coldest temperatures
will occur. Ended up nudging the forecast to the coldest guidance
for the night, which brings readings close to record values, but
still a couple degrees warmer. We may need to look at the need for
a Wind Chill Advisory Sunday night for the plains, as readings are
currently forecasted to be between -15 to -25 degrees, with the
coldest expected over Logan, Phillips and Sedgwick counties.
Moisture in the northwest flow will be decreasing Monday for a
drier day, though will still see scattered orographic snow over
the mountains. Cooled the max temperature forecast over the plains
as northeast winds will keep the arctic airmass in, though
expecting some sun to peak through the clouds to get them into
the teens to low 20s. The warming trend will continue Tuesday as
an upper ridge builds and moves across the state. Look for
temperatures to be about 10 degrees warmer, but still below
normal.
A weather system off the Pacific will push onshore Wednesday to
bring moisture into the mountains in the morning, as well as
a warmer airmass over the state. Temperatures should warm another
10 degrees. Then increasing lift Wednesday night should allow for
a chance of showers over the far northeast plains, where cold air
from the Great Plains surface high will still be found. As that
system kicks out Thursday morning, this will finally push out the
cold arctic air over the far northeast plains. Thursday
temperatures will be another 5 to 10 degrees warmer, though
moisture in the flow will keep snow in the mountains.
Another Pacific system is expected to push onshore Friday for the
next chance of snow forecast area wide. GFS wants to be deepest
and close the trough into a low, which would help wrap moisture
into the plains, whereas the Canadian and EC wants to keep it
open, which would tend to downslope at least the western plains.
Warmer temperatures may allow for rain showers over the plains as
well. EIther way, the mountains are expected to see more snow to
continue to add to the above normal snowpack.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 737 PM MST Sat Mar 2 2019
Snow will decrease after 07Z. However ceilings will remain around
1000 feet with visibility less than 5 miles. Even though not much
snow is expected for Sunday, low clouds, fog, and flurries will
continue to limit visibility. Winds are expected to stay northerly
into Sunday morning. Winds then become light and turn easterly
after 18Z Sunday.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 11 AM MST Sunday for COZ030-032-
037-039>051.
Winter Storm Warning until 11 AM MST Sunday for COZ031-033-035-
036.
Winter Storm Warning until 5 AM MST Monday for COZ034.
Winter Weather Advisory until 11 AM MST Sunday for COZ038.
Winter Storm Warning until 9 PM MST this evening for COZ038.
&&
$$
UPDATE...Meier
SHORT TERM...Dankers
LONG TERM...Kriederman
AVIATION...Meier
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
933 PM EST Sat Mar 2 2019
.SYNOPSIS...
A fast moving low pressure system will spread snow into the
region later tonight and through the day on Sunday. After the
low moves through, a much colder airmass will settle into the
region through the first part of the upcoming week.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HRRR and RAP have picked up on the potential for a stripe of
light precipitation overnight that has been depicted in the GFS
and now NAM as well. Looks like it might be a bit of seeder
feeder that is creating this band that may affect parts of
southwest and south central Ohio. Still a fair amount of
uncertainty, so kept PoPs low. Road temperatures are still
generally in the 40s and model suggests that pavement does not
get below freezing overnight. So even if a quarter inch of snow
falls tonight, it seems that it would have minimal impact.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
Models have finally settled on a more more muted system, with a
southerly track of the surface low through the southeastern
U.S. Isentropic lift ramps up Sunday morning, with snow
overrunning the fa during that time. Expect snow to be the main
ptype Sunday, but locations in the far southeast could see some
rain mix in with the snow during the late morning into early
afternoon. Road temperature forecast models are showing that
road surface temperatures are expected to stay above freezing
throughout the day, which may limit snow accumulations to only
grassy surfaces and maybe overpasses. Updated snow totals have
1-2 inches, approximately south of I-70ish, with the possibility
of some locations making 3 inches. Will issue an advisory I-70
south. The snow could be tapering off in the far west as early
as late afternoon. Highs on Sunday will range in the 30s.
The mid level s/w energy will work quickly to the east Sunday night,
pulling the backedge of the precipitation into the Appalachians.
Snow should be over in the east by midnight. Arctic high begins to
build in late in the night. Temperatures will drop into the mid
teens to lower 20s by morning.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
High pressure and dry conditions will be working into the region at
the start of the long term period. Cloud cover will decrease
through the day, however temperatures will be cool with high
temperatures in the 20s. With clear to mostly clear skies Monday
night temperatures will drop down around 10 to the low teens.
An upper level disturbance will work through on Tuesday allowing for
scattered snow showers. There are steep low level lapse rates and
expect winds to be gusty around 25 to 35 mph. Snow showers will
exit the area by the evening hours. The coolest wind chill values
will be Tuesday night into Wednesday morning with wind chill values
in the negative single digits to single digits.
Dry conditions will then be in place until Thursday morning. Another
system will move through Thursday afternoon into Friday bringing a
mix of precipitation. Another round of precipitation will move into
the region for Saturday.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
Expect MVFR ceilings to spread into the Cincinnati and Dayton
areas during the early part of the TAF period while other
locations are forecast to remain VFR until after 12Z. A fast
moving system will spread snow across all terminals on Sunday.
This will cause prevailing ceilings to drop below 2000 ft with a
period of IFR ceilings and visibility possible. Winds will
generally be out of th north at 10 kt or less.
OUTLOOK...MVFR ceilings will continue into Sunday night. MVFR
ceilings are possible Tuesday.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Winter Weather Advisory from 7 AM to 7 PM EST Sunday for
OHZ053-060>062-070>072-077>080.
Winter Weather Advisory from 10 AM Sunday to 1 AM EST Monday
for OHZ054>056-063>065-073-074-081-082-088.
KY...Winter Weather Advisory from 7 AM to 7 PM EST Sunday for
KYZ089>099.
Winter Weather Advisory from 10 AM Sunday to 1 AM EST Monday
for KYZ100.
IN...Winter Weather Advisory from 7 AM to 7 PM EST Sunday for
INZ050-058-059-066-073>075-080.
&&
$$
SYNOPSIS...JGL/Sites
NEAR TERM...
SHORT TERM...Sites
LONG TERM...Novak
AVIATION...
Area Forecast Discussion
National Weather Service Lincoln IL
912 PM CST Sat Mar 2 2019
.UPDATE...
Issued at 912 PM CST Sat Mar 2 2019
Cloudy skies prevail across central Illinois this evening...with
temperatures mainly in the upper 20s and lower 30s. Surface
analysis shows next storm system slated to impact the region still
well to the southwest over New Mexico. As this low tracks
eastward, snow will spread across the Plains overnight...then
into central Illinois by Sunday morning. 00z NAM and HRRR both
delay onset of precip by a couple of hours from previous forecast,
which seems quite reasonable given presence of sprawling high
pressure ridge from the Northern Plains into the Ohio River
Valley. Have therefore dropped PoPs late tonight except across the
far SW KILX CWA around Jacksonville. Once the atmosphere moistens
from the top-down, snow will quickly spread across the area by mid
to late morning. 00z model trends still suggest the heaviest
snowfall of 1-3 inches will be focused along/south of I-72...with
locations from Peoria and Bloomington northward seeing less than
1 inch.
&&
.SHORT TERM...(This evening through Sunday)
ISSUED AT 226 PM CST Sat Mar 2 2019
Clouds will continue to impact the region tonight through the end
of the weekend, as another weather making system approaches the
Midwest. Current radar returns are indicating precipitation
falling from the sky across central Illinois, however with dry air
still overhead much of this is dissipating before reaching the
ground. The region should remain dry through the evening and into
the overnight.
Models continue to trend slowly with the approaching system, as
well as a slight decrease in total snowfall amounts around the
region. Northerly winds will help to tighten the precipitation
gradient for this system. This will also usher dry air into the
region ahead of the system, meaning saturation will take a little
extra time before precip finally begins to reach the ground Sunday
morning.
Current position of the low remains in the Rockies, but a rapid
ejection of the system will occur this evening as it races through
the Plains and arrives into the mid-Mississippi Valley early
Sunday morning. It will arrive as a disorganized low, before
redeveloping a core in the southeast US. Models agree that
snowfall will start after 12z in the south-western portion of the
CWA. It will then spread to the east north-east through the
morning, with the majority of snowfall occurring along and south
of I-72. Locations north of I-72 are expected to receive up to 2
inches of snowfall, while locations south of I-72 will get 2-3
inches. Surrounding offices to the southwest and south have issued
a Winter Weather Advisory, after understanding this event is on a
Sunday with lowered impacts, I will continue the SPS already
ongoing. This system will quickly move through the region Sunday,
exiting between 00-03z.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 226 PM CST Sat Mar 2 2019
Behind the exiting system, a blast of cold Arctic air will filter
into the Midwest for the first half of the upcoming week. A 1044mb
high will develop across the northern Rockies, and with a tight
pressure gradient, enhanced northwesterly winds will move across
the northern Plains into the Midwest. This will bring another
round of cold air, and frigid wind chills, to the region. Monday
morning lows will be in the single digits, with wind chills around
advisory criteria of -15 to -20 from I-72 northward. At this time
no surrounding offices have initiated a wind chill advisory, but
that will need to be addressed tonight. No issuance was given, as
to not confuse the public with different advisories. Clear skies
will return Monday behind the frontal passage, however
temperatures will be quite chilly in the teens to mid 20s. The low
will drop out of the northern Rockies and deepen as it heads into
the central Plains. This will provide one more frigid night, Monday
into Tuesday, as temperatures dip to the single digits around
much of the area. Westerly winds will remain elevated near
10-15mph, dropping wind chills back into the negative double
digits Tuesday morning.
The high will continue to dominate the region through mid-week
before giving way to another weather producing system.
Temperatures will warm during the second half of the week, as
southerly winds return. However, the region will remain below
normal (mid 40s) for this time of year.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 546 PM CST Sat Mar 2 2019
MVFR ceilings linger at both KBMI and KCMI late this afternoon:
however, these will likely improve over the next couple of hours.
Main aviation weather concern will an approaching storm system
late tonight into Sunday that will spread snow into the area.
Forecast soundings suggest ceilings will lower back to MVFR at
KPIA by 06z...then further east to KCMI by around 12z. Snow will
develop from west to east Sunday morning, but will be heaviest and
most persistent at the I-72 terminals where visbys will be reduced
to around 2 miles. The snow will quickly come to an end between
18z and 22z. Winds will initially be N/NE at around 10kt through
tonight, then will back to NW and increase to 10-15kt by Sunday
afternoon.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Baker
LONG TERM...Baker
AVIATION...Barnes
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1103 PM EST Sat Mar 2 2019
.UPDATE...
Issued at 1103 PM EST SAT MAR 2 2019
Hourly temperature and dewpoint grids were freshened up based on
recent observations and trends. The forecast for the overnight
hours remains on track and no changes were needed at this time.
For Sunday and Sunday night, no changes have been made at this
time.
Much of the event, at least prior to 21Z, will have very low snow
to liquid ratio, well below 10 to 1. Snow to liquid ratios will
be increasing after that from northwest to southeast, but deeper
moisture will also be starting to depart. The 0Z NAM and 18Z NAM
from Sat did indicate the potential for a higher snowfall in a
band near or just south of the Mtn Parkway that develops as the
surface low beings to deepens in the Carolinas late Sunday
afternoon/evening. Confidence in that occurring is low as much of
the other guidance, such as the 18Z GFS from Sat and 0Z GFS and
0Z HRRR however, do not support this. Instead that guidance
supports relatively low amounts for valley locations and somewhat
higher amounts on ridges. For the most part, it still appears
that snowfall will be about an inch or less for the vast majority
of the area. Ridgetops, generally along or north of the Mountain
Parkway, and especially near and north of I 64, may receive
slightly more. Temperatures on average will be coldest in Fleming
County and the Winter Weather Advisory remains in effect there.
An SPS has been issued for the remainder of the area where
impactful accumulating snow is less certain. Later shifts will
evaluate the entire suite of 0Z for any changes that might be
needed.
UPDATE Issued at 744 PM EST SAT MAR 2 2019
Some minor adjustments have been made to hourly grids at this
time. The main change is to adjust temperatures across the higher
elevations closer to recent trends. 18Z guidance supports the
ongoing forecast for the most part through Sunday night. With
temperatures expected to be very marginal if not outright too warm
at times for any accumulations, in the mid 30s to upper 30s in
the north, outside of grassy or elevated surfaces during the early
March day on Sunday, daytime accumulations should be very limited
even there. Precipitation type may also shift back and forth
between rain and snow and forecast soundings indicate that rates
may never be high enough for full wetbulbing of the near surface
layer to closer to the freezing mark. As temperatures begin to
cool late afternoon and evening, at the same time as the deeper
moisture will be shifting southeast some impacts are more
probable. The 18Z HRRR which runs out to 6Z on Monday supports the
ongoing forecast. Ridgetops generally near and north of I 64 will
have the highest chances for accumulations. No changes to the WSW
areal extent or the SPS are planned at this time. 0Z guidance
should shed more light on the event.
&&
.SHORT TERM...(This evening through Sunday night)
Issued at 454 PM EST SAT MAR 2 2019
A messy period of weather is in store. A mid/upper level wave
currently crossing east over the central/southern Rockies will
coincide with a developing northern stream trough and plunge of
arctic air. A wave will develop on a frontal boundary to our south
and bring precip or the JKL forecast area, mainly on Sunday.
Temperatures will be marginal for snow, especially near the
ground. Based on forecast soundings, a mix of rain and snow is
forecast, tending toward more snow in our northern counties, and
largely rain in the south. Even in the north, surface temps a
little above freezing on Sunday will limit accumulations. If the
snow can come down hard enough at times, it will depress the temps
a bit and probably result in slushy accumulations. At this time,
only in Fleming County does it appear that an advisory may be
warranted. One has been issued there for up to two inches,
especially on ridges, and this blends in with advisories from
surrounding offices.
On Sunday evening the deep moisture will be pulling out to the
east as colder air arrives with the departure of the surface low.
Forecast soundings show some potential for freezing drizzle due to
lingering low level moisture where clouds temps are too warm for
ice. This will be monitored, and if it looks like a large enough
threat, it will need to be emphasized more in future forecast
updates.
.LONG TERM...(Sunday night through Friday)
Issued at 413 AM EST SAT MAR 2 2019
A low pressure system tracking to our SE will begin to exit east of
the region Sunday night, pulling the QPF with it and out of the CWA
fairly quickly. With strong northerly flow taking hold at the
surface as the system departs, cold air will begin to filter in from
Canada, and temperatures will fall well below freezing throughout
the overnight. This, coupled with any lingering moisture, will
translate to snowfall. However, given the general consensus between
the latest model runs that the qpf will be exiting the CWA rather
quickly, this will limit accumulations amounts between 0 and 12Z
Monday. The latest forecast is for generally between 0.5 and 1.0
inch, mainly across the eastern CWA. Given the falling temperatures,
some of this snow could adhere to the roads and may cause some
travel impacts.
Once this system exits to our east, upper level troughing will take
hold across much of the central and eastern U.S., with strong
pressure gradients and NW flow into the region. This will couple
with a large area of high pressure moving in from our NW to keep dry
but much colder conditions in place through at least mid week. Highs
Monday will be in the low to mid 30s, and maximum radiational
cooling on Monday night will allow temps to fall into the teens.
Can`t rule out a few single digits in the north and deeper eastern
valleys as well. Temperatures will remain similar through Wednesday.
After this point, the upper level troughing and low heights across
the state will finally shift eastward with the GFS and ECMWF both
showing rising heights across the state. The models then start to
diverge in their solutions, with the ECMWF keeping ridging across
the central U.S. through Friday, while the GFS brings a shortwave
eastward towards the Mississippi River Valley. Either the ridge or the
shortwave will traverse Kentucky Friday night, but depending on
which it is will have major implications on the sensible weather.
Stuck with the Superblend for pops and QPF during this time, but it
does seem to be very heavy on the GFS solution bringing higher pops
across the CWA Thursday night into Friday. Any precip that falls
Thursday night will be in the form of snow with temps below
freezing.
Surprisingly, despite the large differences in the models during
this time period, they actually do come into better agreement about
a upper level low developing across the Rockies and ejecting
eastward towards the Ohio Valley later in the weekend. This system
will weaken as it traverses the Ohio Valley Sunday, but will likely
bring another round of widespread precip to the region just past
the forecast period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 735 PM EST SAT MAR 2 2019
Conditions at TAF issuance were mainly in the MVFR range across
the area with some IFR in the higher elevations right along the VA
border. Although MOS and Lamp data do not indicate, most of the
rest of the guidance indicates at least a brief window of
improvement, with most places becoming VFR by around 03Z to 4Z,
but generally maintaining ceilings from around 3500 to 6000 feet
AGL. This should persist for a few hours, but another
deterioration ahead of the next system back into the MVFR range is
expected around 9Z. Mainly IFR is expected by 15Z. A mixture of
rain and snow should overspread the area 10Z to 16Z, with a
mixture of rain and snow developing. IFR vis and some reductions
to near or perhaps below airport mins are possible at times
thereafter. This will persist through the remainder of the
period.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 7 AM to 6 PM EST Sunday for KYZ044.
&&
$$
UPDATE...JP
SHORT TERM...HAL
LONG TERM...JMW
AVIATION...JP
Area Forecast Discussion
National Weather Service Tulsa OK
933 PM CST Sat Mar 2 2019
...UPDATE...
.DISCUSSION...
Forecast looks to be more or less on track, with freezing line
slowly sinking into northeast OK with areas of ongoing
drizzle/freezing drizzle. Light snow continues to track east
through southwest KS into far northwest OK and this will spread
into the area later tonight. Latest few runs of the HRRR suggest
the snow may arrive a bit later than previous forecast, although
overall amounts look about the same. Expect around a half inch to
perhaps an inch along the TUL-FYV corridor, with higher amounts
closer to the OK/KS and AR/MO borders.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 26 27 8 23 / 90 70 10 10
FSM 38 39 17 30 / 90 80 0 10
MLC 31 32 13 27 / 80 50 0 10
BVO 21 22 6 22 / 100 70 10 10
FYV 31 32 9 24 / 90 100 0 10
BYV 30 30 7 23 / 90 100 0 10
MKO 29 31 10 25 / 80 70 0 10
MIO 24 24 5 20 / 100 100 0 10
F10 28 29 10 24 / 90 60 10 10
HHW 37 39 20 33 / 80 50 0 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Winter Weather Advisory until noon CST Sunday for OKZ054>070.
AR...Winter Weather Advisory until noon CST Sunday for ARZ001-002-010-
011.
&&
$$
SHORT TERM...18