Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/06/21
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1026 PM EDT Wed May 5 2021
.SYNOPSIS...
A cold front will move east of the region into New England
overnight. Winds will become breezy allowing drier air to spread
across the region resulting in a dry day Thursday. The next
chance for some showers arrives Friday, mainly for areas west of
the Hudson River.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
.UPDATE...Cold front now east of the region. Still dealing with
some showers behind the front, as another upper level
disturbance moves through. Showers most likely over the next
couple hours for areas northeast of Albany, with isolated to
scattered showers elsewhere. Winds have shifted to the west-
northwest and increased in wake of the cold front. Showers will
taper off overnight as the last short wave moves east into New
England.
.PREVIOUS [0745]...Cold front continues to gradually move
eastward across the region, although it`s eastward progress has
slowed somewhat as it tracks through the Taconics and into
western New England. This has enabled an area of steady rainfall
to linger along the front. The HRRR guidance has this depicted
well, so have delayed end of rainfall and increased pops from
around Albany northeast through much of the evening.
Once the strengthening northwest flow and cold advection
spreads into our region through the early morning hours and
daybreak, clouds will tend to break up in parts of the Capital
Region and Hudson Valley due to downslope but outside of those
areas, especially in terrain, clouds may be anchored through
much of the night.
Still, with the cold advection and northwest winds becoming
breezy, lows tonight around 40 to mid 40s with mid to upper 30s
higher terrain.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Increasing sunshine through Thursday morning, with areas of
terrain the last to see the clouds breaking up. Northwest winds
and cold advection will limit warming somewhat but strong sun
should help temperatures to reach the upper 50s to lower 60s
with around 50 to mid 50s higher terrain.
Weak high pressure centers itself over our region Thursday night
with winds trending to calm. A mostly clear sky and radiational
cooling conditions should help temperatures to fall steadily.
There is some question as to how much mid and high clouds can
build toward our region ahead of the next system, times for
Friday night and Saturday. However, most of Thursday night
should be mainly clear with lows in the mid to upper 30s and
around 30 to lower 30s northern areas. Some frost headlines may
be needed.
Increasing clouds through the day Friday with light southeast
winds as a complex evolution of the upper pattern begins. One
upper impulse tracks out of Canada, central and western NY/PA
and south of Long Island, while another upper low drops slowly
out of Canada into the Great Lakes behind it through Saturday. A
convergent zone of moisture, lining up with upper dynamics sets
up in a north/south orientation through central NY/PA by Friday
evening and through Saturday morning.
Precipitation should remain mostly west of our region through
the day Friday but extent of thick cloud cover is a bit
uncertain. Highs Friday will depend on how much cloud cover can
extend east into our region. Highs Friday around 60 to mid 60s
with 50s in western areas.
The timing of the precipitation slowly building east is a bit
uncertain but the western Mohawk Valley, southern Adirondacks,
Schoharie Valley and eastern Catskills should see some chances
for cold rain Friday night with even the potential for a few
snow flakes mixed in. The greatest precipitation intensity
within the best convergence and upper dynamics should stay in
central NY/PA, but again, there are some small chances of some
mixing with snow if the more intense precipitation just brushes
western areas. The boundary layer temperatures, above perhaps
2000 or 3000 feet, will be around freezing but H925 should be
warm enough to melt any rain/snow mix to rain in most areas.
During the day Saturday, the precipitation should build east but
the upper dynamics and low level convergence is expected to
weaken. So lighter intensity precipitation/showers with a bit
more limited coverage should affect our region Saturday. Highs
Saturday in the 50s with mid to upper 40s higher terrain.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
The period starts out Saturday night with a short wave trough
exiting to our east. Other than an isolated leftover shower in
the evening, most of the night looks dry and cool. There should
be enough of a breeze to prevent temps from getting cold enough
to worry about any frost at this time, with lows mainly in the
upper 30s in valley locations.
At this time Sunday (Mother`s Day) appears to be dry, as our
area will be sandwiched between an upper low over SE Ontario and
a progressive southern stream wave moving into the mid Atlantic
region. Will only mention slight chance pops in some areas to
the north and south of Albany, although temperatures will be
highly dependent on cloud cover which is uncertain at this time.
For now will mention highs in the 50s to lower 60s, which is
still below normal.
Forecast confidence decreases Sunday night into Monday, as the
sensible weather will be highly dependent on how dominant the
upper trough to the north will be compared to the southern
stream wave. Models split at this time, with the ECMWF
indicating a weaker northern stream trough and thus tracks the
wave of low pressure closer to our area, bringing rainfall to at
least the southern half of our region. However, the GFS and CMC
showing a stronger and more progressive northern stream trough,
which would suppress low pressure farther south and keep
conditions mostly dry except for a few showers associated with
the northern trough. Will mention slight/low chance pops for now
until guidance becomes more clear.
Isolated to widely scattered showers and cool/breezy conditions
expected for Tuesday, as a broad upper level trough settles in
across the Great Lakes and Northeast again. The next chance of a
completely dry and mostly sunny day looks to be next Wednesday,
as model guidance in agreement showing an area of high pressure
building in from the west. Temperatures still expected to be
below normal though.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Cold front continues to gradually move eastward across the
region this evening. Along and just behind the front, rain and
associated IFR cigs are occurring at KPOU/KPSF with VFR/MVFR
cigs at KALB/KGFL farther behind the front. Rain will taper off
between 01Z- 03Z from west to east as drier air starts to filter
in from the west. Conditions expected to improve to VFR at KPOU
first by late this evening, then KALB/KGFL overnight and KPSF
last by early Thursday morning.
VFR conditions expected on Thursday, as a drier air mass settles
in with high pressure building in from the west.
Winds behind the cold front will become west-northwest tonight
around 8-14 kt with occasional gusts around 20 kt increasing to
12-15 kt with gusts to around 20-25 kt on Thursday.
Outlook...
Thursday Night: No Operational Impact. NO SIG WX.
Friday: No Operational Impact. NO SIG WX.
Friday Night: Low Operational Impact. Slight Chance of RA.
Saturday: Moderate Operational Impact. Chance of RA.
Saturday Night: Low Operational Impact. NO SIG WX.
Sunday: Low Operational Impact. NO SIG WX.
Sunday Night: Low Operational Impact. Slight Chance of SHRA.
Monday: Low Operational Impact. Slight Chance of SHRA.
&&
.FIRE WEATHER...
Wind gusts to around 30 mph Thursday afternoon...
A cold front moves through this evening and breezy winds will
allow drier air to spread across the region resulting in a
pleasant Thursday. The next chance for some showers arrives
Friday, mainly for areas west of the Hudson River.
RH values tonight will be above 60 percent but will fall to
around 30 percent Thursday afternoon. RH values increase to
above 60 percent Thursday night and drop to around 40 percent
Friday afternoon.
Light winds this evening will become northwest before daybreak
and increase to 15 to 25 mph through Thursday morning. There
could be gusts to 30 mph Thursday afternoon. Winds diminish to
less than 15 mph Thursday night and become southeast at less
than 15 mph Friday.
&&
.HYDROLOGY...
An additional tenth to third of an inch of rain is expected
through this evening. Then, Thursday and Friday are expected to
be dry. Rivers and stream should rise in response to the rain
over the past few days but should remain within their
respective banks. Our next potential for light precipitation
returns Friday afternoon and night, mainly for areas west of the
Hudson. Precipitation spreads to the rest of our area Saturday.
For details on specific area rivers and lakes,
including observed and forecast river stages and lake
elevations, please visit the Advanced Hydrologic Prediction
Service /AHPS/ graphs on our website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...NAS
NEAR TERM...NAS/JPV
SHORT TERM...NAS
LONG TERM...JPV
AVIATION...JPV
FIRE WEATHER...NAS
HYDROLOGY...NAS
Area Forecast Discussion
National Weather Service Amarillo TX
535 PM CDT Wed May 5 2021
.AVIATION...00Z TAFS...
VFR conditions are expected to prevail at all TAF sites. VCTS
still possible at KGUY through 03Z, if the threat ends earlier
then will pull it from the TAF. Southeast winds will shift
northerly with the cold front passage. GUY/DHT should have the
front passing through right now (00z), with AMA lagging more
closer to 3z. North winds 10-15kts gusting 20-25kts through about
12z then lightening in the 10kt range and coming around out of the
southeast thereafter.
Weber
&&
.PREV DISCUSSION... /Issued 234 PM CDT Wed May 5 2021/
SHORT TERM...Today through Tomorrow Night...
Looking at the current 500mb RAP analysis, the ridge is positioned
over the West Coast with with a disturbance present over the
Rockies and already helping to kick off storms in eastern
Colorado along a surface cold front. Meanwhile a surface trough is
visible on satellite with a cumulus field forming ahead of the
front. Storms may attempt to fire along this boundary early this
afternoon. However, the midlevel disturbance will kick across the
Panhandles later this evening along with the cold front passage,
which will provide additional lifting and cooling to any weak capping
inversion in place right above the surface across the northern
Panhandles. Strong to severe storms are possible, mainly across
the Oklahoma Panhandle and eastern half of the Texas Panhandle.
Instability is present but limited with MLCAPE values of less than
500 J/kg, but bulk shear is around 35 to 45 knots with pockets of
50 knots possible later into the evening hours. Soundings reveal
a fairly dry boundary layer with an inverted "V" shape and very
steep low level lapse rates which indicates a potential for
mostly high based storms with strong or damaging wind gusts. Large
hail cannot be ruled out with some buoyancy present in the hail
growth zone, along with decent midlevel lapse rates present.
Temperatures are warming into the low to mid 70s today with breezy
south southwest winds. Storms will continue to ride the front
into Oklahoma later tonight and be out of the area by the early
morning hours. The surface front is not bringing with it a ton of
cooler air, so temperatures are not expected to be colder than
last night with lows still in the 40s to lower 50s.
Thursday will be a pleasant day as the ridge aloft resides just
west of the Plains with a surface high building over the Southern
Plains. Surface winds will return to the southeast and with this
upslope flow, temperatures will likely not get much above the 70s.
Rutt
LONG TERM...Friday through Tuesday
An upper ridge will build in over the Panhandles Friday with
perturbations embedded in the ridge. One perturbation will track
across the forecast area early Friday and will allow for a round
of convection to exit the Panhandles early Friday with shortwave
trough over the central and southern Rockies approaching the
Panhandles Friday afternoon. Convection expected to develop across
most or all of the forecast area Friday afternoon through Friday
night. Another shortwave trough then expected to track eastward
out of the central and southern Rockies Sunday afternoon into
Sunday night and possibly Monday morning. Convection expected to
develop and increase in areal coverage Sunday afternoon through
Sunday night and possibly as late as Monday morning across most
or all of the Panhandles. Main upper trough will track east across
the Great Basin region and southwestern states and Four Corners
region Monday night through Tuesday and Tuesday night. This upper
trough will bring additional convection to most or all of the
forecast area late Monday night and Tuesday through Tuesday night.
Surface low over southeastern Colorado Friday will bring a cold
front from eastern Colorado across southern Kansas and northern
Oklahoma with a surface trough or dryline across eastern New
Mexico by late Friday. The cold front may remain stationary to the
north and east of the forecast area with the dryline over the
eastern Plains of New Mexico Friday night. Surface low to drop
south into the Panhandles by late Saturday and will usher in the
cold front Saturday evening and Saturday night. Another surface
low to develop on the frontal boundary over the southern Rockies
Sunday with reinforcing surge of cooler air by Sunday night with
the surface pressure gradient tightening up. Gusty upslope surface
flow Sunday into Sunday night through Monday night and Tuesday in
the much cooler and more moist post-frontal air mass regime.
Schneider
&&
.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX 48 78 54 86 60 / 10 0 0 5 20
Beaver OK 45 75 51 90 59 / 30 0 0 5 20
Boise City OK 40 76 51 87 53 / 10 0 0 20 10
Borger TX 52 81 57 90 63 / 20 0 0 5 20
Boys Ranch TX 48 80 55 90 59 / 10 0 0 10 20
Canyon TX 46 79 53 87 58 / 10 0 0 5 20
Clarendon TX 50 77 55 85 62 / 20 5 0 5 20
Dalhart TX 42 77 50 86 52 / 10 0 0 10 10
Guymon OK 44 77 52 89 58 / 30 0 0 10 10
Hereford TX 46 80 54 87 58 / 5 0 0 10 20
Lipscomb TX 46 76 52 88 60 / 40 0 0 5 20
Pampa TX 48 77 54 86 60 / 20 0 0 5 20
Shamrock TX 51 79 52 87 61 / 30 5 0 5 20
Wellington TX 51 80 53 86 62 / 20 5 0 5 20
&&
.AMA Watches/Warnings/Advisories...
TX...None.
OK...None.
&&
$$
89/99
Area Forecast Discussion
National Weather Service Boston/Norton MA
1046 PM EDT Wed May 5 2021
.SYNOPSIS...
Low pressure will reach Nova Scotia and the Canadian Maritimes
by early Thursday. Gusty northwest winds early Thursday trend
lighter by afternoon with seasonable temperatures, sunshine and
dry conditions. Next chance of showers arrives Friday night into
Saturday, as a coastal low pressure passes offshore, although a
washout is not expected. Dry and seasonably mild weather
briefly returns Sunday, before yet another coastal low and rain
possibly impacts the region Sunday night into Monday.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
No major changes to the forecast. Did tweak rainfall chances
overnight based on the last several runs of the HRRR and
observed radar trends. Not expecting temperatures to change
much the rest of tonight. Northwest winds becoming gusty after
midnight.
7 PM Update:
Weak 1002 mb low just southeast of Nantucket per latest obs and
buoys. Back edge of rain shield moving thru the Worcester Hills
and RI, and traversing steadily eastward. Wind shift to the WNW
already across Western CT/MA, and this drier air and subsidence
will continue to overspread the region overnight from west to
east. Thus, a drying trend overnight from west to east. Previous
forecast captures this nicely, so no major changes with this
update. Earlier discussion below.
=================================================================
For tonight, as surface low pulls away, ongoing rains should
trend lighter and more intermittent as light northerly flow
trends northwest. As rain ends by mid to late evening, should
see event total rainfall from a quarter inch or less across
eastern MA and much of RI, with a quarter to nearly one-half
inch across interior western/central MA and across most of
northern CT. NW winds will trend increasingly breezy due to
strengthening isallobaric/pressure gradient and cool/dry
advection helping to steepen overnight lapse rates. Gusts to
25-30 mph developing late in the overnight into the pre-dawn hrs
Thurs. Skies should begin to scatter out especially second half
of tonight, leading to mostly clear to partly cloudy
conditions. 925 mb temps fall to around +1 to +4C. Kept lows in
the 40s, low 40s in the Berkshires and mid/upper 40s elsewhere.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
313 PM Update:
Thursday...
A broad upper-level trough centered over the Midwest will slowly
move eastward on Thursday behind low-pressure and an associated cold
front moving east over the Atlantic ocean. West/northwesterly flow
behind the cold-front will usher in a drier air mass over southern
New England with PWAT values below 0.40". With very little moisture
in the atmosphere we will be looking at mostly clear skies on
Thursday. However, some model guidance has hinted at a small amount
of mid-high level moisture that may allow for a few mid-high clouds
to develop in the afternoon.
A tight pressure gradient between weak high pressure building in
from the west and low-pressure over the Atlantic will relax as the
day progresses on Thursday. This means we`ll begin the day with
somewhat gusty winds that will gradually diminish by the mid to late
afternoon hours. The clear skies and windy conditions should allow
for fairly deep mixing early that will support high temperatures in
the low-mid 60s across most of southern New England on Thursday
afternoon. Despite the breezy conditions to start the day, this is
shaping up to be the most pleasant day of the week as a period of
unsettled weather will continue into the weekend.
Thursday Night...
A quiet evening on Thursday night as weak high pressure will largely
dominate southern New England. Southwesterly flow aloft will advect
moisture at the mid to high levels into the region that will result
in increasing cloudiness overnight. This will limit radiational
cooling and should keep low-temperatures in the low-mid 40s for most
of southern New England by daybreak on Friday. Areas further north
and west where less cloud cover is forecast should see lows dip into
the upper 30s.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
345 pm update...
Highlights...
* A mix of dry and seasonably mild days but also a few rounds of
rain possible
Friday...
Short wave ridging holds on to provide a dry and seasonably mild day
with highs 60-65. Fairly pleasant with partial sunshine and light
winds. Although light onshore flow will keep the coastline in the
mid to upper 50s. By Friday night, upstream northern stream energy
rounds the base of the northeast trough and then enters New England.
This will deepen offshore low but passing well southeast of the
40N/70W benchmark. Nonetheless, this will yield increasing clouds
Fri night with a risk of scattered showers toward morning.
Saturday/Sat night...
As this jet energy moves across New England, downstream the offshore
low continues to deepen into a Gale Center, but the upper flow is
progressive, so the offshore Gale races northeast into the
maritimes. Although, an inverted trough extending back across New
England from the Gale Center, may have sufficient deep layer
moisture and lift to support scattered showers across MA/RI/CT Sat
into Sat evening, but by no means a washout with periods of dry
weather too.
Sunday...
Fast/progressive upper flow continues, with short wave ridging
advecting across New England, providing dry and seasonably mild
weather. Expecting at least partial sunshine, a modest west wind 10-
20 mph and highs 60-65.
Next Week...
Northern stream remains active and may spawn another frontal wave
with its rain shield potentially impacting Southern New England
Sunday night into Monday. Cool but dry weather may follow behind
this departing wave for Tue/Wed.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
Forecaster Confidence Levels.
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Tonight: High confidence in trends. Moderate confidence in
exact timing.
Generally, the theme for improving conditions continues. Most
areas trending dry by 06/06Z. Expect IFR to MVFR during this
period. Drier NW winds will lead to more substantial W-E
improvement in categories after 06Z, with most areas becoming
VFR around 09Z, except across Cape Cod where MVFR type ceilings
may linger.
Winds become NW and increases in speed to around 8-15 kt, with
increasing gusts to 20-25 kt.
Thursday: High confidence.
VFR. Gusty/blustery NW winds around 10-15 kt, gusts to 20-27 kt
into the morning, with speeds decreasing into the aftn. Outside
chance at coastal sea breeze late in the day if p-gradient
diminishes as quick as some guidance indicates.
Thursday Night:
VFR. Light NW/WNW winds.
KBOS TAF...High confidence in trends, but moderate in timing.
KBDL TAF...High confidence in trends, but moderate in timing.
Outlook /Friday through Monday/...
Friday: VFR.
Friday Night: VFR. Breezy.
Saturday: Mainly VFR, with areas MVFR possible. Breezy. Chance
SHRA.
Saturday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Sunday: VFR. Breezy.
Sunday Night: Mainly VFR, with areas MVFR possible. Breezy.
Chance SHRA.
Monday: Mainly VFR, with areas MVFR possible. Chance SHRA.
&&
.MARINE...
In terms of marine headlines, Small Craft Advisories continue
for rough seas and gusty winds up to 30 kt. Strongest gusts
across the coastal waters east of MA.
For tonight: Rain and fog decreases, visibilities improving
from half-1 mile to unrestricted by mid tonight. N winds around
10 kt become NW and increase to 10-20 kt with gusts to 25-30 kt
by the pre-dawn hrs, strongest on the eastern waters. Seas 2-4
ft.
For Thursday: NW winds 10-20 kt with gusts 25-30 kt thru the morning
hrs, then decrease to around 10 kt with gusts around 15 kt for the
aftn. Seas 2-3 ft on the eastern waters, around 3-5 ft on the
southern offshore waters.
For Thursday Night: NW winds around 10 kt trend N/NE at similar
speeds, gusts 10-15 kt. Seas 2-3 ft.
Outlook /Friday through Monday/...
Friday: Winds less than 25 kt.
Friday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain showers.
Saturday: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers.
Saturday Night through Sunday: Winds less than 25 kt. Seas up
to 5 ft. Chance of rain showers.
Sunday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Rain showers likely.
Monday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 6 AM to noon EDT Thursday for ANZ230-
231-250-251.
Small Craft Advisory until 8 PM EDT Thursday for ANZ254>256.
&&
$$
SYNOPSIS...Nocera/Loconto/RM
NEAR TERM...Belk/Nocera/Loconto
SHORT TERM...RM
LONG TERM...Nocera
AVIATION...Belk/Nocera/Loconto/RM
MARINE...Belk/Nocera/Loconto/RM
Area Forecast Discussion
National Weather Service Dodge City KS
634 PM CDT Wed May 5 2021
...Updated Aviation...
.SHORT TERM...(This evening through Thursday)
Issued at 250 PM CDT Wed May 5 2021
HRRR model showing quite a number of storms along the cold front
that will move into the area by mid afternoon and exit the southeast
counties during the early evening. Widespread severe weather isn`t
expected however the HRRR model has shown consistency on
producing explicit near severe to exceeding severe criteria
thunderstorm outflow wind. Through collaboration with SPC, the
marginal severe weather risk area is extended even further east of
the Dodge City area though this evening. Numerous 30 to 50 mph
gusts are likely in the uncapped areas downwind of the focus of
convective development. As the storms developing along the cold
front begin producing cold pools or localized downbursts, the
uncapped region down stream may see a few storms developing in
advance of the gust front. Rain cooled outflow should drop
temperatures quickly over the eastern sections of the area; into
the 50s by early evening while the far southwest sections enjoys
more mild upper 60s well into the early evening hours.
Models suggest the cold front stalls out over north central Kansas
into west central Kansas this evening , and with the moisture left
over from the exiting storms, the later evening and overnight could
possible see some fog developing despite light southwest winds - a
mesoscale problem better diagnosed later this evening.
Thursday should shape up to be a much quieter weather day as the
center of surface high pressure settles over the central/southern
High Plains areas from the KS/CO line into north Texas.
.LONG TERM...(Thursday night through Wednesday)
Issued at 250 PM CDT Wed May 5 2021
Welcome to Summer in May on Saturday. There is still a range of high
temperatures (mid 90s to as low as mid 80s) among the models and
this may be caused by the frontal position or storm development
timing. Saturday also looks interesting for potential supercells
near a dryline and warm front intersection in central Kansas -
which may not linger long for our area, or remain to the east
altogether as the convection quickly moves east into eastern
Kansas.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 628 PM CDT Wed May 5 2021
VFR flying conditions are expected this TAF period for all
terminals. Lingering convection along a weak cold front moving
through southwest Kansas has cleared HYS and GCK, and will clear
DDC and LBL in the next hour. Winds will remain light and variable
through tomorrow under the influence of weak surface high
pressure.
&&
.FIRE WEATHER...
Issued at 250 PM CDT Wed May 5 2021
Cooler weather conditions in the near term will preclude very low rh
and therefore fire weather concerns. Hot and potentially much drier
condition will return however, mainly over the most western areas of
the forecast area by friday and heading into Saturday. Look for
gusty winds into the 30 to 40 mph range as early as late morning
Friday and through the day, with relative humidity falling to as
low as around 20 percent in the far west.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 43 71 48 86 / 30 0 10 10
GCK 40 71 47 87 / 30 0 0 0
EHA 42 76 52 90 / 40 0 0 10
LBL 42 74 49 89 / 50 0 0 10
HYS 43 68 44 79 / 30 0 10 10
P28 46 72 47 82 / 60 0 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Springer
FIRE WEATHER...Russell
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Sioux Falls SD
1026 PM CDT Wed May 5 2021
.SHORT TERM...(This Evening through Thursday)
Issued at 231 PM CDT Wed May 5 2021
Area of WAA driven showers continues to move eastward through NW
IA/SW MN this afternoon and should exit the area by evening.
Meanwhile, a surface low currently analyzed along the MO River in SE
SD/NE Neb has provided enough forcing for an arcing line of weak
thunderstorms through NE Neb which may drift toward our far SE SD
counties and eventually Hwy 20 in NW IA. Mid afternoon RAP
mesoanalysis suggest roughly 200-500 J/kg of SBCAPE in this area and
while quite unlikely, with a bit of enhanced near surface vorticity,
the main concern would be the (small) potential for a brief
funnel/landspout with any convection. Meanwhile further west, a
second cluster of weak convection in south central SD may
occasionally produce gusts to around 50 mph with a dry subcloud
layer noted in the soundings.
Surface high pressure drifts down to through central SD overnight
and will set up the potential for frost producing temperatures. A
few question marks remain however in regards to cloud cover with a
few model solutions hanging on to either a mid level deck or worse
yet, a low stratus deck. Areas south of I-90 seem to be favored for
this cloud contamination but SREF probabilities for reduced ceilings
are not overly impressive. For this reason, have kept overnight lows
roughly near the 50th percentile which still produces widespread
lower to mid 30s over about the northwest 2/3rds of our forecast
area. With dewpoint depressions supportive of frost, have issued a
Frost Advisory for this area as well.
Quiet conditions return for Thursday with added sunshine and
afternoon temperatures in the 60s. While the better SPG remains to
our east, still could see some gusts in the 20-25 mph range. Of more
important note is various forecast soundings showing 25-30 mph of
wind at the top of the mixed layer along the Buffalo Ridge, which
combined with RH values in the lower to mid 20s, could result in
enhanced fire weather concerns. After collaboration with our fire
weather partners, have held off on any headlines given the recent
rainfall and greenup.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 231 PM CDT Wed May 5 2021
Ridge axis shifts east for Friday with continued quiet conditions
across our immediate area. Again, temperatures in the 60s look to be
a good bet although perhaps a bit cooler across SW MN where a weak
backdoor cold front and north/northeasterly winds may keep
temperatures in the upper 50s.
Attention for Saturday turns to cut off low dropping through the Pac
NW. The main baroclinic zone as well as instability axis looks to
remain to the southwest of our forecast area and thus the better
convectively enhanced rainfall amounts should remain void of our
area as well. There is still a fairly good zone of broad synoptic
lift further east however and thus lighter showers could still very
well be in the mix for at least the western half our area. Last few
deterministic runs of the global models have shown a southwestward
shift with the QPF axis which is supported by the ECMWF ensemble as
well. In either case, outside of maybe the GFS, does not look like
any rainfall amounts would make a significant impact to our ongoing
drought.
For Sunday into early next week, previously mentioned cutoff low
wobbles across the intermountain west while a second cut off sinks
toward the Great Lakes region. This leaves our region in an area of
muddled shortwave ridging. Temperatures will likely remain on the
cool side of normal with mid 50s to mid 60s fairly common.
Precipitation chances also look to remain minimal.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1021 PM CDT Wed May 5 2021
MVFR ceilings will continue to shift eastward but may still impact
areas along and east of a FSD to SUX line before 12z. Otherwise
VFR conditions should prevail through the forecast period. Expect
north winds to gradually weaken overnight as sfc high pressure
builds in. Winds will increase with mixing Thursday morning.
During the afternoon, expect gusts up to 25 kts and diurnally
driven mid level cumulus.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Frost Advisory from 3 AM to 8 AM CDT Thursday for SDZ038>040-050-
052>069.
MN...Frost Advisory from 3 AM to 8 AM CDT Thursday for MNZ071-072-080-
081-089-097-098.
IA...Frost Advisory from 3 AM to 8 AM CDT Thursday for IAZ001.
NE...NONE.
&&
$$
SHORT TERM...Kalin
LONG TERM...Kalin
AVIATION...BP
Area Forecast Discussion
National Weather Service Jacksonville FL
928 PM EDT Wed May 5 2021
...LULL IN CONVECTION THIS EVENING WITH NEXT ROUND FOR NE FLORIDA
THURSDAY MORNING...
.UPDATE...
A thermal trough and outflow boundary produced scattered showers
and a few strong t`storms this evening just north of the I-10
corridor and across the JAX metro area as an upper level impulse
crossed overhead. The highest measured convective wind gust was
38 mph at NAS JAX with a reported gust estimate of 50-55 mph
across the JAX Southside.
The bulk of deeper convection has shifted offshore and weakened
this evening under speedy westerly flow of 25-30 kts. The 00z JAX
RAOB indicated plenty of elevated instability as well as surface
based instability nosing inland from the GOMEX to continue a
chance of showers and thunderstorms through the night as a cold
front across central GA approaches. The best potential for precip
through midnight will focus across SE GA near the approaching front,
then as the surface front approaches NE FL toward sunrise Thursday
morning, expect an increase in precipitation coverage and intensity
as the parent mid/upper level trough axis deepens overhead. Leaned
toward SPC HREF guidance for precip update as the HRRR performed
poorly this evening.
The best potential for stronger storms Thursday will focus
generally south of I-10 after sunrise through mid-afternoon
Thursday where bulk shear of near 35 kts will phase over elevated
surface based instabilty that edged across north-central FL from
the GOMEX just ahead of the surface front. Gusty winds and small
hail will be possible in a few stronger storms.
Mild, muggy low temps tonight will only cool into the upper 60s to
low 70s across much of NE FL, then following tomorrow`s cool
front, lows Thu night will cool by about 10 degrees back toward
climo values.
&&
.MARINE...
A weak trough axis drifting offshore of the local coast this
evening was bringing variable winds less than 10 kts across the
local waters. Updated the forecast to reflect this trend, then
continued to advertise westerly winds after midnight generally 10
kts as the main cold front slides southeast across the local
waters. Combined seas were running 3 ft or less. Shower and
thunderstorm activity is expected to increase in coverage from the
west Thursday morning, with a few strong storms possible through
Thursday afternoon.
Rip Currents: Low risk through Thursday.
&&
.CLIMATE...
A new daily record high of 96 was set at Craig Airfield today.
This broke the previous record for the date of 93 last set in
2003.
&&
.PREV DISCUSSION [740 PM EDT]...
.Short Term.../through Thursday night/...
Cold front will be located to the north of the forecast area through
this evening, as an upper wave moves northeast across SE GA. Expect
isolated showers and storms this afternoon, with a better chance
this evening as the wave moves through.
The front will dip into SE GA around midnight, then to near the
GA/FL line around dawn. Convective chances will continue through the
night due to frontal convergence.
The boundary will slowly move southeast across NE FL through the day
Thursday. Precipitation chances should end by midnight Thursday
evening, as high pressure builds in from the west northwest.
Best potential for stronger and possibly severe storms through
Tonight will be across SE GA, with this potential more over NE FL
during the day Thursday.
Temperatures will be above normal Tonight, but trend a little below
normal Thursday due to expected precipitation and cloud cover.
Temperatures will trend a little below normal northwest Thursday
night, while remaining near to a little above normal southeast.
.Long Term.../Friday through Wednesday/...
Surface high pressure will continue to build from the west northwest
through the day Friday, yielding a dry northwest flow. It is
expected to be a sunny day with highs a little below normal.
The high will build overhead Friday night into Saturday morning,
then to the east Saturday afternoon. Subsidence under the ridge will
continue the dry weather with below normal temperatures.
The high will move more toward the east southeast Sunday. This
pattern will yield flow more from the south. This will bring warmer
and more humid air back into the region, with highs trending above
normal. At this point Sunday still looks like a dry day with
precipitation chances too low to mention, but an isolated shower
or storm can not be ruled out due to sea breeze convergence and
diurnal heating.
A cold front will sink into the southeastern US Monday, with a
chance for showers and storms ahead of it. This boundary is
expected to settle near the FL/GA line Tuesday, and remain nearly
stationary through Wednesday. Waves of energy will move along this
boundary, leading to an unsettled period. The potential for
strong to severe storms will exist in this Monday to Wednesday
timeframe.
.AVIATION...
[Through 00Z Friday]
Unsettled pattern through the end of the TAF period with clusters
of showers and storms expected to periodically impact the
terminals. Through 06z, SSI, JAX, CRG and potentially VQQ will
have the higher potential for TSRA and restrictions. After
midnight, rainfall potential will continue at JAX, CRG and VQQ and
increase at GNV and SGJ through early Thu morning. Most terminals
will fall to MVFR tonight due to low clouds, even outside of
precipitation areas, with a continuation of prevailing MVFR
ceilings through mid-late afternoon Thu until drier air filters
in behind frontal passage. Latest SREF guidance continued to
favor best potential of IFR to potentially LIFR/VLIFR at GNV 09z-
12z tonight with some low stratus edging inland from the GOMEX,
and continued to trend toward prevailing IFR with a hint of
SCT002. Conditions at GNV will likely improve to prevailing MVFR
12-14z Thu as precipitation potential increases ahead of
approaching cold front.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 67 81 57 77 50 / 40 20 0 0 0
SSI 71 78 62 78 58 / 50 50 10 0 0
JAX 71 82 61 82 54 / 40 60 20 0 0
SGJ 72 85 64 82 59 / 20 70 20 0 0
GNV 71 83 61 82 53 / 30 70 20 0 0
OCF 72 86 63 83 55 / 20 70 20 0 0
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1102 PM CDT Wed May 5 2021
.UPDATE...
Issued at 1006 PM CDT Wed May 5 2021
The forecast looks on track for the rest of the night. New short
range guidance is trickling into the office, and everything
continues to point to a band of showers and thunderstorms
developing over central or east central Missouri along or just
ahead of the cold front by mid-morning and moving southeast
through the day. Latest RAP shows between 1000-1500 J/Kg of MUCAPE
ahead of the front coupled up with 25-35kts of 0-6km shear, and it
looks like most of that shear is in the lowest 3km. Soundings
don`t look particularly favorable for large hail, but a
marginally severe wind gust is possible since the boundary layer
looks pretty dry, and any downdrafts will get a boost from
evaporative cooling. The threat for any strong/severe storms
should be ending by 22-23Z as instability drops below 500 J/Kg in
our southeastern counties.
Carney
&&
.SHORT TERM... (Through Late Thursday Night)
Issued at 220 PM CDT Wed May 5 2021
The diurnal cumulus cloud field across southwestern IL will
dissipate early this evening with the loss of daytime heating.
More cloud cover will advect southeastward into the entire
forecast area later this evening and overnight as a northwest flow
shortwave approaches. An associated cold front, currently across
portions of Nebraska and Kansas will move southeastward through
our forecast area late tonight and Thursday. Scattered light
showers can be expected across northeast MO and west central IL
towards early morning. More significant showers along with a few
storms can be expected Thursday afternoon across southeast MO and
southwest IL as the front intercepts better boundary layer
moisture. Instability will also be more favorable due to daytime
heating and relatively cold mid level temperatures in the upper
level trough axis to steepen the lapse rates. Could not rule out a
few strong storms with small hail and strong wind gusts. The
scattered showers/storms will shift out of the forecast area by
early Thursday evening. There will be below normal low temperatures
Thursday night due to cold air advection behind the cold front
along with a clearing sky, diminishing winds, and lowering surface
dew points for good radiational cooling.
GKS
.LONG TERM... (Friday through Next Wednesday)
Issued at 220 PM CDT Wed May 5 2021
Warmer temperatures along with dry conditions can be expected for
Friday. This dry weather will be short lived as low-mid level
warm advection north of a developing warm front brings elevated
convection, mainly to central and southeast MO late Friday night
into Saturday morning. There will be strong low level moisture
convergence in this area on the nose of a southwesterly low level
jet. The chance of rain will increase Saturday night as the front
becomes nearly stationary across our forecast area with shortwaves
inducing weak areas of low pressure along the front aiding in low
level convergence and convective initiation. There will be the
potential for locally heavy rainfall Saturday night into Sunday
morning. The threat for showers/storms will shift south of our
forecast area by Sunday night as the front drops south of the
region. Temperatures will be unseasonably cold Sunday night into
the next work week as a strong surface ridge of high pressure
over the Northern Plains builds southward into the region.
GKS
&&
.AVIATION... (For the 06z TAFs through 06z Thursday Night)
Issued at 1054 PM CDT Wed May 5 2021
Not much change in the forecast since previous TAF issuance. VFR
flight conditions are expected to prevail for the remainder of
the night. The cold front looks on track to move into northeast
Missouri and west central Illinois around 10-12Z Thursday morning.
A band of MVFR ceilings is likely in the vicinity of the front.
There will likely be some widely scattered showers in the morning
ahead of the front, but latest guidance is showing the showers
congealing into a band with some embedded thunderstorms ahead of
the front over central or east central Missouri around 15-16Z and
continuing southeast through the area. Some gusty winds and hail
are possible with the strongest storms. Precipitation should be
out of the area by 00Z.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Marquette MI
741 PM EDT Wed May 5 2021
.SHORT TERM...(This evening through Thursday)
Issued at 408 PM EDT WED MAY 5 2021
WV imagery and RAP analysis indicated a mid/upper level low over
northwest Ontario with a broad trough through the central CONUS. One
weak shortwave trough was moving off to the northeast of Lake
Superior while another moving through southwest Minnesota supported
an area of rain through srn MN. Steep low level lapse rates to 700
mb and favorable low level convergence along the Lake Superior
breeze boundary triggered some light showers/sprinkles over inland
portions of central Upper Michigan which have diminished after
moving into or toward Lake Michigan. Otherwise, even with partly to
mostly sunny skies, with the cool airmass in place temps have
struggled through the 40s north and into the lower 50s south.
Tonight, after diurnal cu fade, expect mostly clear skies except
over the far south where clouds from the MN shrtwv brush the area.
Favorable radiational cooling conditions will allow temps to fall
into the upper 20s to around 30 inland with mid 30s along the Great
Lakes.
Thursday, with steep sfc-700 mb lapse rates similar today,
scattered/isolated showers should develop with daytime heating
close to Lake Michigan where the low level convergence is
strongest. Another shrtwv approaching from the northwest late may
help spread showers toward the west late. With 850 mb temps in the
0C to -2C range, temps should be a little higher with readings
from the upper 40s north to the mid 50s south.
.LONG TERM...(Thursday night through Wednesday)
Issued at 344 PM EDT WED MAY 5 2021
The long-term pattern continues to look the way it has for the past
several days. A closed upper-level low is forecast to remain
anchored near James Bay through at least Sunday with multiple short
waves passing through the flow around it for the next few days. By
Tuesday, ridging is expected to build in the Northern Plains and
then shift east towards the Upper Great Lakes.
Thursday night, the strongest of many short waves embedded in NW
flow will be dropping down from near Lake Winnipeg across Minnesota
and Wisconsin. Models have had a fairly consistent precip signal
with this feature - mainly for the west half and south central,
although the 12z EC brought the precip axis farther north through
the Keweenaw and Marquette. The GFS and NAM are a most aggressive
with QPF with over 0.30" in spots, though all models at least show a
stripe of generally 0.10" or so. Model wet bulb zero heights drop to
as low as 500 feet AGL in model soundings, especially interior west.
While the cloud cover and precip will keep lows Thursday night
warmer than what the NBM spit out, it may still be cold enough to
get a light slushy snow accumulation, especially if a brief band of
heavier precip materializes as is suggested by the 12z GFS. The best
chance for that looks to be along a line from Ironwood to Iron
Mountain.
On Friday, that wave will pull out but a second wave behind it may
kick off a few more isolated rain showers. CAA behind the wave will
drop 850 mb temps to around -6 C. Even with clouds beginning to
clear in the afternoon, this will still make for a seasonably chilly
day with highs mostly in the mid 40s. Saturday looks a few degrees
warmer with models indicating more sunshine and thus deeper mixing.
Once again, could see a rogue rain shower or two in the afternoon
with the cold air aloft and subtle waves embedded in the NW flow.
Have manually drawn in slight chance POPs across the central U.P. to
account for that possibility.
Sunday and Monday look dry, but still cool, as the core of the ULL
dislodges Saturday night and drifts south towards Lake Superior.
Highs on Sunday should continue to be mostly in the 40s. Right now
this forecast has temps warming on Monday back into the upper 40s to
mid 50s. However the models have trended a bit cooler aloft for
Monday so it`s possible that those temps end up coming back down to
right around where they`ll be on Sunday. 60s will then return to
most of the area Tuesday and Wednesday as ridging builds in from the
west.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 728 PM EDT WED MAY 5 2021
A persistent upper-level low pressure trough will allow periods of
mid-level clouds to linger over the terminals during the period,
but VFR conditions will prevail. Expect light to moderate lake
breezes to develop during the day on Thursday.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 408 PM EDT WED MAY 5 2021
A quiet period is expected to linger over the region for the
remainder of the week and into the weekend with winds below 20 knots
expected.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...RJC
AVIATION...Voss
MARINE...JLB
Area Forecast Discussion
National Weather Service Paducah KY
702 PM CDT Wed May 5 2021
.UPDATE...
Issued at 702 PM CDT Wed May 5 2021
Updated aviation discussion for 00Z TAFs.
&&
.SHORT TERM...(Tonight through Friday)
Issued at 306 PM CDT Wed May 5 2021
Patchy clouds continue to form and stream through the Quad State
this afternoon from the NNW. These clouds have kept temperatures
lower than expected, mainly in the low to mid 60s. Cloud cover
will finally diminish during the evening to mostly clear skies.
An upper-level trough will dig into the midwest through tomorrow.
Low pressure crosses ESE-ward from Iowa to Ohio, dragging a cold
into Southern Illinois mid-morning Thursday, crossing the Quad
State through the rest of the day and early evening. The front
will bring showers and a chance of storms to the area. Models have
trended to a more organized structure with this line, especially
the HRRR (which is also one of the more progressive models with
the front). Instability is fairly low (order of 500 J/kg for
MLCAPE) and shear is adequate (25-30 kt). While dew points are
rather low, only around 50, but mid-level lapse rates will be a
robust 7-8 C/km. As a result, a marginal risk of severe weather
has been included for most of the Quad State for this line of
storms. Ahead of the front, winds shift to the south, lifting
highs tomorrow to the upper 60s to near 70.
Ridging starts to build into the Quad State Thursday night, which
will counteract the cold frontal cooling and leave lows/highs
Thursday Night/Friday similar to Wednesday Night/Thursday. Friday
will provide a brief return to dry weather ahead of the next
system.
.LONG TERM...(Friday night through Wednesday)
Issued at 306 PM CDT Wed May 5 2021
A wet signal is setting up, not unexpected, given the WPC All
Hazards outlook for heavy rain. As the high amplitude pattern
becomes more quasi-zonal with time, we`ll see first, a warm front
lift north across the area late Friday night into Saturday. This
brings the first shot of wet weather, but instability is lacking or
elevated at best. Surface dew points still in the 40s Friday night
begin to nudge their way into the 50s through the course of the day
Saturday. Average QPF Friday night-Saturday on the order of about
1/4 inch is expected with the warm fropa.
The warm front`s lift gets to a position somewhere along the Lower
Ohio River and hangs, until the parent Low brings the cold front
in/across the FA. We see better destabilization occur in the warm
sector Saturday night-Sunday, ahead of the approaching cold front.
Warm conveyor showers/storms may provide impetus for better
localized heavy rainfall, which again for now, looks to be across
our Lower Ohio River Valley portion of the FA. QPF on the order of 1-
2 inches for average amounts occur during this Saturday night-Sunday
time frame, with some localized 2+ inch amounts potential. The cold
front sweeps across the FA late Sunday-Sunday night, effectively
ending the pops from northwest to southeast with its passage. Maybe
another 1/4 to 1/2 inch occurs coincident.
A pause it rain chances occurs after this Sunday night cold fropa,
but how much of a pause is a question. The deterministic GFS
suggests maybe a dry start to the week, but the Blend of models
smooths the noisier signals to a low chance cat start to the week.
What comes together with time is the next trof/weather system
impacting a wetter forecast by the mid week time frame, thereby
producing a `wetter with time` approach to the back end of the long
term portion of the forecast.
&&
.AVIATION...
Issued at 702 PM CDT Wed May 5 2021
VFR conditions are expected through much of the forecast period.
Light and variable winds tonight will become southwesterly around
10 knots ahead of an approaching cold front on Thursday. Scattered
showers and thunderstorms are expected to develop along and ahead
of this front during the late morning and into the afternoon.
Winds could be strong and gusty in the vicinity of thunderstorms.
Winds will shift to the west/northwest during the afternoon in the
wake of the front.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...RJP
SHORT TERM...ATL
LONG TERM...DH
AVIATION...RJP