Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/13/19
Area Forecast Discussion
National Weather Service La Crosse WI
652 PM CDT Sun May 12 2019
.SHORT TERM...(Tonight through Monday Night)
Issued at 130 PM CDT Sun May 12 2019
GOES water vapor and RAP 500mb analysis showing a closed low sinking
southeastward into northern MO. Meanwhile, weak troughing/cooler air
aloft was over our area with broken cumulus/stratocumulus resulting
in the fairly steep lower level lapse rates. So far, radar has been
quiet but a few showers through the remainder of this afternoon
cannot be ruled out. Otherwise, a chilly Mother`s Day afternoon with
temperatures at 1 pm ranging from the 55-60 degree mark.
Look for the cumulus/stratocumulus to dissipate after sunset with
high pressure building in. Lows tonight will range from the middle
30s across central WI -where some frost is possible, to the upper
30s/lower 40s elsewhere.
Mid-level/surface ridge of high pressure build in for Monday for a
nice beginning of the new work week. Under mostly sunny skies, plan
on temperatures climbing well into the 60s.
Surface high slides southeast of the area Monday night, setting up
increasing warm air advection/moisture transport over the Plains
into IA. All models showing a batch of showers firing in this
WAA/moisture transport over the Dakotas, sliding southeast into are
as west of the Mississippi River toward morning. Better CAPE will
stay over the Plains, so thinking this will be a decaying area of
showers/isolated storms as they approach the area. Overnight lows
are expected to be in the 40s.
.LONG TERM...(Tuesday through Sunday)
Issued at 130 PM CDT Sun May 12 2019
Models in good agreement with a weak mid-level trough/surface cold
front moving southeast through the region for Tuesday into Tuesday
night, bringing in a chance of showers and isolated thunderstorms.
Storms appear to be rather innocuous at this time as CAPE pool stays
bottled up over the Central Plains. Otherwise, highs Tuesday look to
be right around normal, peaking in 65-70 degree range.
Mid-level ridge amplifies over the central CONUS/Upper Mississippi
River Valley region Wednesday int Thursday for some warming
temperatures. Plan on highs well into the 70s, maybe a few lower 80s
for Thursday. Will have to watch for the potential of showers and
storm dropping out of the Northern Plains Thursday but thinking
bulk of it should stay deflected to the north of our forecast area.
Friday into next weekend looks increasingly active as the ridge
starts breaking down allowing deep warm/moist flow into the area
along with a warm frontal boundary in the vicinity. Could see
multiple rounds of shower and storms in this scenario. Otherwise,
remaining warm with highs Friday/Saturday in the mid 70s/lower 80s
and lower/mid 70s Sunday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 651 PM CDT Sun May 12 2019
VFR conditions will continue through the TAF period. BKN diurnal
mid-level cloud deck is already beginning to erode and will give
way to mostly clear skies overnight with high pressure overhead.
Light and variable winds expected through most of the period,
perhaps becoming calm for awhile overnight. Despite this favorable
setup for fog, there does not appear to be enough low level
moisture to promote its development. Will leave it out of the
TAFs and monitor trends this evening. A ridge of high pressure
slides across the area Monday afternoon. This will lead to
continued light winds backing from the WNW to the SW, along with a
SCT to BKN stratocu deck developing again.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...Kurz
Area Forecast Discussion
National Weather Service Quad Cities IA IL
621 PM CDT Sun May 12 2019
...00Z AVIATION UPDATE...
.SYNOPSIS...
Issued at 258 PM CDT Sun May 12 2019
Upper level low pushing across the area was producing an area of
light rain across mainly our southern cwa, where the better
forcing was located. PWATs were only around 6 tenths of an inch.
Rainfall amounts will generally be around a tenth of an inch or
less. Cloudy skies were keeping temperatures once again well below
normal for mid May, only in the upper 40s to mid 50s.
&&
.SHORT TERM...(This Evening through Monday)
ISSUED AT 258 PM CDT Sun May 12 2019
Tonight: Lingering showers in our se cwa will end early this
evening. This will be followed by subsidence in the wake of the
departing upper low and surface high pressure building into the
area, will allow skies to clear overnight. Combined with light
winds, temperatures should drop to the upper 30s at most
locations. Some favored cold spots in valleys may experience
patchy frost.
Monday: Models suggest a sunny morning followed by increasing
cu/sc in the afternoon, especially in our eastern counties. The
HRRR indicates isolated showers popping in the afternoon in nw
IL but confidence is low so have opted to keep the forecast dry
for now. The sunshine should push afternoon temperatures into the
mid 60s for a pleasant day.
.LONG TERM...(Monday Night through Sunday)
ISSUED AT 258 PM CDT Sun May 12 2019
Weak disturbances the first half of the week will bring a risk of
some rain to the area but it should be mainly spotty and light. A
change in the weather pattern points to warmer than normal
temperatures developing with increasing chances for rain next
weekend.
Monday night
Assessment...high confidence
Quiet and dry conditions will be seen as high pressure moves into
the Ohio Valley while an upper level disturbance approaches from the
Plains. Temperatures will average below normal.
Tuesday and Tuesday night
Assessment...medium confidence
An upper level disturbance will move through the area bringing a
risk of rain. Daytime heating may allow some isolated thunderstorms
to develop during the afternoon and evening. Overall moisture
availability will dictate the areal coverage of any rain.
Right now the model consensus has slight chance to chance pops on
Tuesday with chance pops Tuesday night.
Wednesday
Assessment...medium to high confidence
The model consensus has dry conditions for the area as high pressure
builds into the western Great Lakes. Temperatures will average
slightly above normal.
Wednesday night on...
Wednesday night
Assessment...high confidence
Quiet and dry conditions will be seen as high pressure moves east
into the Great Lakes and Ohio Valley. Temperatures will average at
or above normal.
Thursday
Assessment...low confidence
Another upper level disturbance will move through the area in the
flow aloft. The better forcing to act upon the moisture available is
across Wisconsin so that raises questions on the areal coverage of
any rain. Areas north of I-80 has a better chance for rain.
Right now the model consensus has slight chance to chance pops for
most areas north of I-80 with dry conditions south of I-80.
Thursday night and Friday
Assessment...low confidence
Starting Thursday night and continuing into next weekend the global
models diverge on their solutions in regards to the sensible
weather.
On the large scale all agree in developing an upper low over the
Rockies with an upper level high over the southeast United States.
Such a pattern places the Midwest in southwest flow aloft. Southwest
flow aloft means much warmer temperatures for the area along with
increasing humidity levels and thus increased chances for rain.
The GFS has rain associated with the upper level disturbance that
exits the area during the evening but then develops new convection
along a stalled front late Thursday evening into Friday.
The CMC global has no rain with the upper level disturbance exiting
the area. Some isolated convection does develop across Iowa
Thursday night with Friday being dry. The front remains across
Minnesota and Wisconsin.
The ECMWF has rain associated with the upper level disturbance
exiting the area Thursday evening. Some convection develops along
the front that moves into Missouri and southern Illinois. The ECMWF
keeps Friday dry for the area.
The FV3 has limited rain associated with the upper level disturbance
exiting the area Thursday evening but has a warm front moving
through the area. The FV3 has Friday mainly dry.
Given the large differences between the global models, the model
consensus is biased toward the GFS solution. The model consensus has
slight chance to chance pops across the soutwest two thirds of the
area Thursday night with dry conditions on Friday. Temperatures will
average above normal.
Friday night
Assessment...low confidence
The differences between the global models continue Friday night and
the one key is where the front is located.
The ECMWF has dry conditions with the front slowly moving back north
as a warm front. The CMC global has the front well north of the area
with only isolated convection developing. Interestingly, both the
ECMWF and CMC solutions point to an atmosphere with a warm layer
aloft preventing convection from developing.
The FV3 keeps the front well north of the area with only limited
weak nocturnal convection developing across the area. This scenario
suggested a capped atmosphere as well but not to the extent of the
ECMWF and CMC. The GFS moves the front back north as a warm front
and develops convection along it.
If one takes into account the moist bias of the GFS the overall
extent of nocturnal convection would be lower. The model consensus
shows this with only slight chance pops north of I-80, and, also
keeps the front north of the area.
The model consensus `could` be slightly underdone with the rain
chances. The strength of the warm layer aloft will dictate the
overall chance for rain.
Saturday through Sunday
Assessment...medium to high confidence on more active weather and
warmer than normal temperatures. Low confidence regarding the areal
coverage and timing of precipitation.
Next weekend the only thing the models agree reasonably well upon is
for warmer than normal temperatures. They vary considerably in
regards to rain chances. The key factor in the rain potential
appears to be related to the depth and position of the upper low.
The ECMWF has a deep upper low over the Rockies that is slow to
eject into the Plains. As a result it keeps the area mainly dry
Saturday with rain moving into the area Saturday night and Sunday
with the next system.
The CMC global is not as deep with the upper low but does have it
further west and north over the Rockies with a slower ejection into
the Plains. The CMC does develop some diurnal convection Saturday
afternoon but keeps the area dry Saturday night with rain moving
into the area on Sunday with the next system.
The GFS and FV3 are not as deep with the upper low over the Rockies.
As a result both eject the next system into the Plains faster. The
GFS and FV3 both develop convection during the day Saturday and then
maintain it to varying degrees as the next system arrives Saturday
night into Sunday.
The model consensus is biased toward the GFS solution and has slight
chance to chance pops Saturday with chance pops Saturday night and
Sunday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
ISSUED AT 621 PM CDT Sun May 12 2019
Rain associated with a passing upper level low will exit the
region early this evening, giving way to slowly clearing VFR level
clouds. High pressure at the surface will provide light and
variable winds overnight. Depending on trends with clearing skies
and lingering low level moisture, there will be the potential for
fog late tonight into Monday morning. Confidence in just how thick
or widespread fog will be is low at this time. Thus, a period of
MVFR visibilities was introduced at all sites as a middle of the
road placeholder, and trends will be watched closely for later
updates. Monday, conditions will be VFR once any early morning fog
clears with light winds and partly cloudy skies.
&&
.HYDROLOGY...
Issued at 1140 AM CDT Sun May 12 2019
The most recent rise on the lower Rock river from heavy rain over
a week ago is ending. Both Moline and Joslin are leveling out will
will begin to fall soon.
Minor rises will be seen on the Cedar, Iowa and Wapsipinicon
rivers as heavy rain across Minnesota over a week ago continues to
move downstream.
On the Mississippi the river continues to fall. LD11 is now below
flood stage and Camanche has fallen to minor flood stage. Heavy
rain that fell over a week ago across Minnesota and Wisconsin will
be working downstream this week. This additional water will create
either a very minor rise or slow down the rate of fall.
Looking ahead while there are some chances for rain this week it
will be spotty with light amounts. Thus river levels are not
expected to be impacted.
Looking further ahead toward next weekend the global weather
models are suggesting the weather pattern will turn more active.
However the weather models disagree on potential rainfall amounts.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Haase
SHORT TERM...Haase
LONG TERM...08
AVIATION...Sheets
HYDROLOGY...08
Area Forecast Discussion
National Weather Service Peachtree City GA
725 PM EDT Sun May 12 2019
.UPDATE...
Updated for the 00Z Aviation Discussion.
&&
.PREV DISCUSSION... /Issued 311 PM EDT Sun May 12 2019/
SHORT TERM /Tonight through Monday Night/...
MCV continues to rotate through the southern sections of the
forecast area providing the focus for a line of showers and
thunderstorms. A few warnings have been issued but activity is
quickly translating eastward and should be out of the area within
the next couple of hours. Further north, areas of North GA have
been dealing with low clouds for much of the day resulting in
limited instability. Only recently have we seen temps get into the
70s. This is allowing for slightly increased instability and with
the forcing of the approaching frontal boundary, shower activity
is increasing.
Models differ on the potential for this area of showers to blossom
into an actual line of convection. The HRRR develops a line once
activity gets to the ATL metro late while the NSSL WRF indicates
barely a line of showers. As such, will continue to just advertise
mid range chance pops for now for later this afternoon along with
mainly isolated thunderstorm activity.
Generally clearing conditions overnight although with all the
rain, could see some patchy dense fog conditions develop in the
wind sheltered areas mainly. Much cooler conditions anticipated
with low to mid 50s by Monday morning for the northern tier.
Should be an outstanding Monday in store with cooler and drier
conditions under a developing full sun. Have been in a summer type
pattern for quite a while so the respite will be quite nice. Very
cool though for this time of year Monday night with some mid 40s
across the far NE sections.
Deese
LONG TERM (Tuesday through Sunday)...
Dry and seasonably cool conditions will prevail Tuesday as the area
continues to be influenced by deep long-wave trough over the eastern
half of the CONUS. An embedded disturbance will drop southeast and
affect parts of the area as early as Wednesday (12z GFS and ECMWF
are a bit slower than NAM). Regardless of timing, moisture is rather
limited so do not expect any widespread/significant precip with this
system.
Upr ridge begins to build from the west toward the end of the work
week which will allow temps to warm back up above normal for this
time of year. A deeper upr trough / storm system will approach the
central and northern High Plains by the weekend, which will likely
enhance the upr ridge over the Southeast. No definitive features to
support any organized convection at this time.
DJN.83
&&
.AVIATION...
00Z Update...
Two bands of showers still progression across the forecast area.
They are diminishing and will go with VCSH at all sites for the
first few hours this evening. Cigs will remain VFR this evening
however expect MVFR cigs to develop, mainly across ATL/AHN late
tonight. All cigs will become VFR by mid to late morning Monday
and remain VFR. Winds will be northwest through the forecast,
becoming gusty Monday afternoon.
//ATL Confidence...00Z Update...
Medium on MVFR cigs late tonight.
High on the rest of the forecast.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
Athens 59 76 51 74 / 60 5 0 0
Atlanta 59 75 52 73 / 30 5 0 0
Blairsville 52 67 44 67 / 20 10 0 0
Cartersville 56 74 49 72 / 20 5 5 0
Columbus 62 80 55 77 / 30 5 0 0
Gainesville 57 73 50 72 / 30 5 0 0
Macon 62 80 53 78 / 60 10 0 0
Rome 55 74 48 73 / 20 5 5 0
Peachtree City 58 76 51 74 / 40 5 0 0
Vidalia 68 83 58 80 / 40 20 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...17
LONG TERM....Thiem
AVIATION...17
Area Forecast Discussion
National Weather Service Indianapolis IN
1133 PM EDT Sun May 12 2019
.UPDATE...
The AVIATION section has been updated below.
&&
.SYNOPSIS...
Issued at 212 PM EDT Sun May 12 2019
An upper level low pressure system will pass through the Region
tonight. This will result in more cloudy...cool and wet weather
overnight and on Monday morning.
High pressure will then build across Indiana and the Ohio Valley
on Monday afternoon...passing across the state through Tuesday.
This will bring dry weather...along with warming temperatures each
day.
Rain chances will return on Wednesday as another area of low
pressure arrives in the Ohio Valley. Chances for rain will persist
on Wednesday through the end of the work week.
&&
.NEAR TERM /Rest of Tonight/...
Issued at 942 PM EDT Sun May 12 2019
Forecast is in pretty good shape. An upper low will bring rain
mainly to the northern forecast area tonight. Tweaked hourly PoPs to
match current conditions and latest hi-res model data, but overall
trends remain the same. Made some minor adjustments to temperatures
but no significant changes made.
Previous discussion follows...
Surface analysis early this afternoon shows low pressure in place
across West Virginia...providing broad cyclonic flow across
the region. Cool NE surface flow was in place across Indiana.
Meanwhile aloft a weak upper level weather disturbance will
pushing some scattered showers across Indiana. Water Vapor Imagery
shows an upper low over Iowa and Missouri.
Models tonight show the upper level low to the west will progress
across Indiana tonight. Lower level moisture remains plentiful as
this feature passes...as seen within the time height sections and
the forecast soundings. Time heights show weak forcing aloft as
the upper low passes. HRRR suggests a wave of light showers
passing across the forecast area...particularly focused across the
northern half of the forecast area. Furthermore...abundant lower
level moisture and weak forcing should also be able to produce
some drizzle. Thus will trend toward light rain and drizzle...with
best chances across the northern parts of the forecast area late
tonight. Given the expected clouds and rain chances will trend
lows at or above the forecast builder lows.
&&
.SHORT TERM /Monday through Wednesday/...
Issued at 212 PM EDT Sun May 12 2019
GFS and NAM show the upper low exiting the region on Monday
afternoon as NW flow begins to develop aloft. Forecast soundings
show lower level clouds lingering for much of the day before
stronger subsidence arrives near 00Z. Thus much of the day looks
to be clouds...with decreasing clouds in the last afternoon as
subsidence builds. Will limit any precip chances to the morning
hours associated with the departing upper low.
Ridging aloft over the western plains is set to develop on Monday
night into Tuesday...resulting in lee side subsidence and high
pressure building across Indiana and the Ohio valley on Tuesday.
Forecast soundings on Tuesday into Wednesday go dry. Thus will
trend toward a dry forecast on Tuesday and Tuesday night.
By wednesday the surface high is expected to drift east of
Indiana as warmer and more humid southerly flow develops on the
backside of the high. meanwhile aloft within the NW flow a short
wave is suggested to approach. Forecast soundings respond showing
good lower level moisture through the day. Thus will include pops
on Wednesday as these features approach.
&&
.LONG TERM /Wednesday Night through Sunday/...
Issued at 303 PM EDT Sun May 12 2019
The broad upper trough that will keep cooler conditions across
much of the eastern U S for the first half of the week will lift
out during the latter part of the work week and eventually be
replaced by a strong ridge as an upper low sets up over the
Rockies then shifts into the High Plains over the weekend. The
result will be a transition back to much warmer temperatures over
the Ohio Valley by the weekend with 80s anticipated for highs
Friday through Sunday over much of the area.
Much drier conditions are expected throughout the extended with
just a few threats for scattered convection. The first will come
late Thursday into Friday as a frontal boundary slides into the
region then lifts north as a warm front...with the second coming
during the tail end of next weekend as low pressure tracks into
the western Great Lakes.
&&
.AVIATION (Discussion for the 130600Z TAF Issuance)...
Issued at 1133 PM EDT Sun May 12 2019
Poor conditions expected overnight, then improvement to VFR during
the daylight hours of Monday.
An upper low will continue to bring low clouds and patchy light
rain/drizzle to the area overnight. Not expecting much in the way of
visibility restriction, but MVFR/IFR ceilings will prevail. Lowest
ceilings are expected to be at KIND/KBMG, and these may vary at
times between IFR and MVFR.
After the low passes to the east Monday, a gradual improvement to
VFR is expected from west to east during the day.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...Puma
NEAR TERM...Puma/50
SHORT TERM...Puma
LONG TERM....Ryan
AVIATION...50
Area Forecast Discussion
National Weather Service Memphis TN
1100 PM CDT Sun May 12 2019
.UPDATE...
Updated to increase rain chances in the short term and add
thunder.
&&
.DISCUSSION...
HRRR not painting the proper picture with convection this evening.
The line has been able to sustain itself...producing wind gusts
of 27-32kts and rainfall amounts near a half inch. Have updated
the late evening forecast to account for increased rain chances
along the Mississippi River and added a slight chance for a few
cracks of thunder. Then kept a slight chance for showers over a
majority of the eastern counties during the overnight hours.
JAB
&&
.PREV DISCUSSION... /issued 626 PM CDT Sun May 12 2019/
UPDATE...Aviation Discussion.
PREV DISCUSSION... /issued 300 PM CDT Sun May 12 2019/
A cool Spring day is underway across the Mid-South. Temperatures
are generally in the low to upper 60s across the entire area under
mostly cloudy skies. Latest surface analysis places a cold front
from Cape Girardeau, Missouri, southwest through Jonesboro,
Arkansas and back through the ArkLaTex region. The front will
continue to push through the Mid-South through this evening.
Simultaneously, a longwave trough will pivot across the northern
half of the forecast area through tomorrow morning. With limited
moisture in place, only light and scattered showers are expected
through midnight across the area. Thereafter, skies will clear out
and temperatures will fall into the lower 50s areawide. A few
places near the Tennessee River may even drop into the upper 40s.
Monday through Friday...
A pretty good stretch of weather is in store for the Mid-South
through this period. Surface high pressure will build into the
region on Monday. Sunny skies will return and temperatures will
warm into the upper 60s to lowers 70s. Tuesday will be nearly
identical with slightly warmer temperatures during the day. High
pressure will slide east by Tuesday night and winds will turn back
around to the south.
Synoptic models are consistent with a frontal boundary moving into
the Mid-South late Tuesday night into Wednesday and spawning
showers across the north. This front is expected to stall
somewhere near the I-40 corridor during the day on Wednesday.
With a humid airmass in place, good chances for diurnally driven
showers and thunderstorms are possible. For now, kept about 30-40
POPs as models differ on coverage at this point. By Thursday, the
upper level ridge will build in across the area and keep the Mid-
South effectively capped through Saturday. Expect highs in the
low to mid 80s and increasing humidity through next weekend. The
models differ on timing of the next system, but showers and
thunderstorms are a good bet by late Sunday at this point.
AC3
&&
.AVIATION...00Z TAFs
There are a few showers approaching JBR, but coverage should
diminish over the next few hours. VFR conditions should prevail at
all sites for the next 24-30 hours. Winds North to Northwest
3-6kt.
30
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1007 PM EDT Sun May 12 2019
.SYNOPSIS...
A cold front will slowly approach from the northwest tonight
and push offshore Monday. Cool high pressure will build in from
the west through midweek. A cold front with limited moisture
will cross the area late week. High pressure will build over the
area next weekend.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
As of 955 PM Sun...Dry across the region with regional rdrs
showing band of shra/tsra well to the NW. High res mdls and
quick look at 00z NAM show mainly dry weather rest of the night.
Lowered pops to slight chc most areas with low chc nrn tier
late with front approaching. With continued SSW flow, overnight
lows will continue mild in the mid to upper 60s inland and
around 70 beaches.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
As of 335 PM Sun...Though deepest moisture will be displaced by
drier westerly flow, the combination of a strong mid level
trough and surface cold front moving through the area should
trigger scattered showers and thunderstorms mainly in the
afternoon. The guidance is forecasting a persistent area of low
clouds through the morning limiting heating/destabilization but
if some insolation develops ahead of the front, a few of the
storms could be strong with gusty winds. Highs will be in the
upper 70s to lower 80s.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
As of 3 PM Sunday...Dry and much cooler weather expected through
mid week, then generally dry with a building heatwave expected
by late week and into next weekend.
Monday night through Thursday...Cyclonic flow aloft continues
through mid week with an upper low tracking from New England
to the Canadian Maritimes and several embedded shortwaves moving
through the flow aloft.
By Mon evening, the cold front will be offshore with low
pressure lifting off the New England coast. Could see lingering
showers, mainly across eastern sections, in the evening, then
cool and dry air filters in through the overnight. Lows will
drop back to below climo for a change, in the low/mid 50s
interior, with upper 50s along the beaches.
Surface high pressure builds in from west through Wed, then
slides offshore Wed night and Thu. Mainly dry weather is
expected through Wed with comfortable dewpoints in the 40s.
Temps will be several degrees below climo with highs around
70-75 inland to upper 60s OBX. Lows expected in the mid to
upper 40s inland to mid 50s along the coast.
A shortwave through digs southeastward on lee side of longwave
Wed night and Thu, trough has limited moisture to work. A few of
the 12z models show light QPF, so cannot rule out a few
showers, but if anything develops will be very widely
scattered. A moderating trend in temps expected as flow begins
to become zonal with sfc high offshore. Temps expected to rise
to near climo, with lows in the low to mid 50s Wed night. High
Thu expected in the upper 70s to lower 80s interior to the mid
70s beaches. Lows Thu night mid/upr 50s inland to low 60s
beaches.
Friday through Sunday...High pressure and upper ridging is
progged to build in late in the week and over the weekend
bringing generally dry weather and warming temps and could see
highs approach 90s over the weekend. However, the 12z
operational GFS and EC now show a final shortwave and backdoor
cold front crossing the area Friday night into early Saturday
with a few light showers pushing across the area, but will wait
to see if this trend continues in the models before buying into
this solution. These models also flatten the upper ridge as it
migrates from the Mississippi River Valley to the eastern CONUS
with not quite as warm temps across the region.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Short Term /through Monday/...
As of 645 PM Sun...Mainly VFR thru evening with brief lowering
in wdly sct to sct convection. Cigs expected to grad lower to
MVFR/IFR late tonight and early Mon morn. Ceilings will
improve Mon afternoon with scattered showers and thunderstorms
possible ahead of a cold front moving through the area.
Long Term /Monday night through Friday/...
As of 345 PM Sunday...Any lingering showers across the region
will push offshore Monday evening with pred VFR conditions
across rtes. High pressure builds into the area through the
rest of the week with pred VFR conditions expected.
&&
.MARINE...
Short Term /through Monday/...
As of 955 PM Sun...Earlier convection disrupted the gusty SSW
winds along the cst. HRRR and 00Z NAM keep winds over nrn tier
and Pamlico Sound below 25 kts so have dropped SCA Sounds and
nrn wtrs. Winds will likely remain gusty off the central and
srn wtrs with some 6 foot seas poss.
Prev disc...SCA`s are in effect for all of the coastal waters
and Sounds. Latest obs show SW winds 20-25 kt with gusts to 30
kt this afternoon and seas 3-5 ft. Deteriorating conditions
through this evening as gusty southerly winds produce seas of 4
to 7 ft. Gusty SW winds will continue into Mon morning with
winds becoming westerly 15-20 kt south of Oregon Inlet/Pamlico
Sound. Winds will become N/NW towards evening as a cold front
crosses the waters late. Seas will continue 4-6 ft south of
Oregon Inlet through the day.
Long Term /Monday night through Friday/...
As of 4 PM Sun...High pressure builds into the are through mid
week. N/NW winds around 15-20 kt Mon evening diminishes to NW
around 10-15 kt overnight into Tuesday. Seas around 3-5 ft and
up to 6 ft across the central northern waters Mon evening,
subsides to 2-5 ft Tue. The upper level trough axis crosses
the area late Tue/Tue night which will serve to tighten the
gradients across the waters with NW winds increasing to 15-20 kt
with higher gusts. Gradients quickly weaken Wed with winds
diminishing from 10-20 kt early to less than 10 kt and seas
subsiding to 2-4 ft northern waters and 1-3 ft southern waters
in the afternoon as high pressure builds across the area. The
high becomes centered offshore Thu and Fri with SW to W winds
around 15 kt or less with seas around 2-4 ft.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...Small Craft Advisory until 2 AM EDT Tuesday for AMZ152-154.
Small Craft Advisory until 9 PM EDT Monday for AMZ156-158.
&&
$$
SYNOPSIS...MHX
NEAR TERM...RF
SHORT TERM...JME
LONG TERM...SK
AVIATION...RF/SK
MARINE...RF/JME/SK
Area Forecast Discussion
National Weather Service Marquette MI
734 PM EDT Sun May 12 2019
.SHORT TERM...(This evening through Monday)
Issued at 312 PM EDT SUN MAY 12 2019
WV imagery and RAP analysis indicated mid/upper level troughing from
Hudson Bay into the central CONUS where a closed low was circulating
near the mid-Mississippi Valley. Weak forcing ahead of a shortwave
lobe extending through this trough into northern MN and the central
Plains was helping to support instability cu and some isolated showers
into far western Upper Mi today. At the surface, high pressure
extending from northern Quebec into the northern Great Lakes has
resulted in light winds and mostly sunny skies across much of the
rest of Upper Michigan with the exception of an area of cumulus
clouds over the eastern counties. Afternoon temps have generally
been in the 50s with a few lower 60s readings.
Tonight, after instability cu dissipates this evening, favorable
radiational cooling should allow min temps to drop into mid to upper
20s over some the favored interior central cool spots and into
generally the lower to mid 30s elsewhere.
Monday, the mid-level trough axis shifts east and will be replaced
by rising 5h heights from the west. Still expect some diurnal cu to
form but dry conditions will prevail. With sfc high pressure in
place, expect lake breezes to prevail, but it likely won`t be until
late in day that the lake breeze develops off Lake MI. Away from
lake moderation, temps will reach the mid and upper 60s.
.LONG TERM...(Monday night through Sunday)
Issued at 231 PM EDT SUN MAY 12 2019
Well, WFO Marquette is currently on its longest streak of days (236)
with high temperatures remaining below 70 degrees. As the forecast
stands now, Tuesday is our next best shot at reaching the 70 degree
mark, with temperatures expected to reach the mid to upper 60s.
Cloud coverage and timing with expected cold front will be a key
factor. Steady SW winds will help combat any type of Lake Superior
breeze that tries to form, though areas north of Lake Michigan may
not appreciate that as temperatures will be suppressed down in the
50s. The last time the office has seen temperatures above 70 degrees
was back on Sept. 17th, when we reached 80 degrees. Normal
temperatures at this point in May are now into the low 60s; May so
far has been about 10 degrees below normal.
Looking deeper into this Tuesday, a surface low will pass to the
north through NW Ontario and into Hudson Bay as an associated trough
and cold front pass across Lake Superior and Upper Michigan.
Depending on the model, rain showers will begin across western UP in
the afternoon or evening, with the GEM beginning closer to mid day
and GFS sometime after dinner. Stay tuned to future forecasts for a
clearer picture. A rumble or two is possible with a few hundred J/kg
showing up on convective based models; however, 60 hours out on
convective-allowing models can often introduce more moisture and
instability than what will actually occur. Overall, QPF ranges from
0.10-0.25 inches, highest amounts with the NAM. After the fropa,
some clearing is expected Wednesday as high pressure builds in,
though not expecting much of a cool down from cold front except for
temperatures near Lake Superior with usual N to NW flow behind front.
The next chance for precipitation comes later Wed night into Thurs
morning as a shortwave approaches from the Canadian Prairies. The
ECMWF comes in much slower bringing precip into the UP Thur night
into Fri morning. QPF values look similar to the precip on
Tuesday night. As the weekend comes closer, a large area of
surface high pressure develops in the Canadian Arctic stretching
an extensive ridge S to SE towards Upper Michigan. The forecast
becomes a bit tricky here as global models come to an agreement on
the high pressure across northern Canada, but it still remains
unclear on how this will affect an approaching low pressure from
the Central Plains. Current model forecasts show this high
pressure serving as a blocking mechanism for the approaching low
pressure and associated precipitation, keeping most precipitation
to the south and west on Saturday. On Sunday, 12Z GFS shows a low
pressure system crossing Upper Michigan bringing widespread rain
throughout the CWA with some areas forecast to exceed the 1 inch
mark. The ECMWF and GEM track further to the west, but bring
similar QPF values expected across the Northland and Arrowhead in
Minnesota. &&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 732 PM EDT SUN MAY 12 2019
The benign weather conditions for aviation interests will continue
through this TAF period at all three terminals. VFR conditions
will prevail with light to calm winds, especially overnight, and
a diurnally-driven CU field tomorrow.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 312 PM EDT SUN MAY 12 2019
Winds will generally be 20 knots or less into much of next week as
surface high pressure dominates into Tuesday and then a couple of
weak cold fronts move through mid to late week.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...JAW
AVIATION...lg
MARINE...Voss
Update to aviation forecast discussion.
&&
.SHORT TERM...(THIS EVENING THROUGH Tuesday NIGHT)
ISSUED AT 201 PM CDT SUN MAY 12 2019
Upper level low over northern Missouri is forecast to slide east
and open up overnight tonight. Scattered showers and thunderstorms
were on-going at this time near the low. HRRR output suggests
scattered to isolated showers and thunderstorms are possible over
SEMO and parts of southern Illinois and Indiana until shortly
after midnight tonight. Freezing levels of 6-8K ft would suggest
small hail is possible in the stronger showers/storms.
Surface high pressure should control our weather through Tuesday
with cool nights and increasingly warm days.
During the day Tuesday and into Tuesday Night an upper level ridge
builds over the central part of the country. A piece of energy
caught in northwest flow will slide down into our area Tuesday
Night. This will bring a chance of showers and possibly a few
thunderstorms during that time. Mainly elevated thunderstorms with
decent K indices and little surface based CAPE.
.LONG TERM...(Wednesday THROUGH Sunday)
ISSUED AT 201 PM CDT SUN MAY 12 2019
The primary forecast concern in the long term is the potential for
showers and thunderstorms on Wednesday, then again by the latter
half of next weekend. Forecast confidence through much of the long
term is higher than average, but decreases with greater model
variability next weekend.
Showers and some elevated thunder will likely be scattered across
the area Wednesday morning as a weak disturbance streams through the
northwesterly flow pattern. Previous thinking was that energy from
the disturbance may time out with peak afternoon heating to refire
scattered thunderstorms across the area Wednesday afternoon and
evening. However, the latest guidance seems to suggest that the best
chance for showers and thunderstorms may occur Wednesday morning,
with chances lowering and/or moving largely south of the region by
afternoon and evening tied to remnant MCV and boundary interactions
from the morning convection. Will still carry small chances during
the afternoon and evening, especially across the southern half, in
case anything were to fire.
The forecast from Thursday through Saturday is largely dry and much
warmer as an upper level ridge over the Plains builds east into the
Mississippi, Ohio, and Tennessee River Valleys through Saturday.
While a mid level capping inversion should tend to limit convective
updrafts, it`s not out of the realm of possibility that an isolated
shower or thunderstorms could develop, especially along the leading
edge of the incoming warm sector Thursday afternoon.
The ECMWF and CMC are markedly stronger than the GFS with the ridge
by the weekend, with the ensemble means supporting each operational
model`s depiction. As a result, the GFS is also faster to bring the
potential for showers and thunderstorms back into the region by
Saturday night and Sunday as energy associated with an upper level
trough over the Plains approaches. The model blended forecast will
carry at least a small chance for showers and thunderstorms late
Saturday night and Sunday.
As the upper level ridge builds east, expect a warming trend through
late week. Highs in the upper 70s on Wednesday should warm well into
the 80s through late week. Likewise, lows in the upper 50s Wednesday
night should slowly moderate into and through the 60s heading into
the weekend.
&&
.AVIATION...(FOR THE 00 TAFS THROUGH 00Z Tuesday)
ISSUED AT 737 PM CDT SUN MAY 12 2019
Mainly VFR conditions at KCGI/KPAH with MVFR/IFR at
KMVN/KEVV/KOWB. Light showers or drizzle impacting KEVV/KOWB will
move east over the next few hours. Other showers are inbound that
might affect KCGI, KMVN and KPAH this evening. Plenty of low
level moisture around for the next 24 hours but the problem will
be figuring out cloud heights. Expecting conditions to be VFR
later tonight at our eastern sites that are now MVFR. As we head
toward morning though, there is some suggestion that we could go
back down. Played the forecast fairly optimistic but did linger
VFR cigs through a good chunk of the day tomorrow. We will re-
evaluate cigs again at the 06Z fcst.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
Area Forecast Discussion
National Weather Service Blacksburg VA
1135 PM EDT Sun May 12 2019
.SYNOPSIS...
A weak cold front will cross the region from the west tonight
followed by a stronger secondary cold front early Monday. This
will result in continued rounds of showers and storms into
tonight along with added showers on Monday as an upper level
area of low pressure slides across the area. Cool high pressure
will follow bringing cool temperatures on gusty northwest winds
by Monday afternoon into Tuesday.
&&
.NEAR TERM /THROUGH MONDAY/...
As of 1133 PM EDT Sunday...Stationary front/wedge boundary
extends roughly as far south as the Roanoke River per wind shift
in regional METARs with radar showing scattered showers across
central VA into Southside. A few of which have some in-cloud
lightning associated with them, though lightning trends have
been downward and should continue to do so. Weakening of this
activity is highly probable as this shifts eastward into eastern
Virginia over the next hour to 90 minutes.
Though light west-northwesterlies generally prevail across the
foothills and westward, aloft the region is still in a
southwest flow and this will help keep clouds around and the
threat of isolated to scattered showers going into the
overnight. We`re still several more hrs away - at least not till
sunrise - until the primary upper level trough begins to
intrude into our forecast area. A re-blossoming of showers then
should occur by daybreak as a shortwave trough rounding the base
of the upper trough - this feature seen in WV imagery over
southern Illinois - pivots into our area. Opted to raise
temperatures and lows up some 2-4 degrees given delayed onset of
sharper cooling and at least mostly cloudy skies.
Previous discussion from this afternoon...
Low pressure in northern West Virginia and western Pennsylvania
has push the warm front a little north this afternoon. Meanwhile
Surface cold front is just to the west of the mountains. The cold
front will travel east tonight into Monday.
Scattered showers and thunderstorms will develop across our area
this afternoon into tonight. Extensive cloud cover and a westerly
wind has hindered convection. However, the combination of
isentropic lift, deep moist southwest wind flow, dynamic forcing
from shortwave aloft and orographic lift will create showers
and thunderstorms.
This morning 12z RNK sounding showed a healthy PWAT at 1.46 inches.
PWATs within this airmass with a deep southwest flow are more
indicative of mid-summer. Deep convection this afternoon can be rain
efficient with locally heavy rains. However, the moderately sheared
environment will caused the heavier convection to be transient.
Because of the movement of storms and spring greening will hold off
on any flash flood watch. FFG is relatively high and coverage
scattered.
SPC Convective Day One outlook has pushed the marginal risk for
severe weather a little farther south. Now, it highlights
southern and eastern portions of our forecast area with a
marginal risk. SPC Mesoscale Analysis at 18z showed SBCAPE has
risen to 1000 to 1500 east of the Blue ridge. The supercell
composite parameter paint the best chance of severe to our east
across eastern Virginia and eastern North Carolina. It still
looks like some of the storms this afternoon into tonight could
be strong to severe. In a moderately sheared environment, with
storm relative 0-3km helicity in the 150 to 200 range,
conditions do support rotation for thunderstorms that gain any
depth aloft, and especially so if they are co-located along a
boundary. For this afternoon into tonight shaped pops towards a
blend of the HRRR and NAM. Most solution indicated the best
chances across southern portions of the forecast area. Low
temperatures tonight will range from the mid 40s in the
northwest mountains of Greenbrier county in West Virginia to
near 60 degrees in the piedmont.
Upper low will move east through the southern Great Lakes Monday
into Monday night. This will keep a persistent flow of cool air and
low level moisture on strengthening northwest flow. The result will
be upslope clouds and showers persisting in the west. While in
the east, a gradual improvement is expected with downsloping
flow. A gusty northwest wind Monday afternoon should remain
below wind advisory levels. High temperatures on Monday will
vary from the upper 40s across the north to the lower 70s in the
piedmont.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 255 PM EDT Sunday...
Strong cool advection will continue Monday night into Tuesday morning
as an upper low passes north allowing surface low pressure to deepen
off New England. Pressure gradient between this feature and high
pressure to the west should keep gusty northwest winds in place as 850
mb temperatures also cool to near 0 deg/C over the mountains by early
Tuesday. This trajectory looks to dry out eastern sections per
downsloping Monday night, while low level moisture combined with the
cool advection and northwest flow likely to keep some upslope showers
going northwest ridges into Tuesday. Lows Monday night mainly 40s with
a few 30s deeper valleys, but overall not as cool as guidance due to
continued mixing. Moisture will decrease further Tuesday as high
pressure builds in although likely Tuesday night before the pressure
gradient decreases. This along with cold air aloft should make for a
very cool/blustery day for mid May on Tuesday with highs only
50s/60s despite increasing sunshine.
High pressure finally builds overhead Tuesday night into Wednesday with
dry air making for a very cool overnight before slowly modifying during
the day as warming aloft ensues. Appears great radiational cooling to
allow temperatures to bottom out by Wednesday morning with lows well
into the 30s in the deeper valleys, with upper 30s to mid 40s
elsewhere. This may be enough to support some patchy frost in
the coldest locations but likely quite spotty at best and only
in the mountain valleys if at all given the warm ground/wetness.
Highs Wednesday rebounding through the 60s to near 70 mountains
and low/mid 70s east. Airmass should modify enough despite
clear skies to see lows stay a bit warmer Wednesday night, but
still 40s to low 50s, with isolated 30s in the deepest valleys
again overnight.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 100 PM EDT Sunday...
Lingering northwest flow aloft will continue to start the period
followed by a transition to mid level ridging and much warmer weather
for next weekend. This scenario should result in passage of another
weak surface cold front Thursday before seeing high pressure offshore
start to dominate under the southeast ridging above. Moisture again
limited within the northwest flow with the front, so appears only
a few showers possible mainly mountains on Thursday. Airmass
will then dry out Friday into Saturday as subsidence increases
before dewpoints start to rebound by Day7 under return flow aloft.
This looks to also tap into much warmer air to the west that
should advect east as the flow aloft turns more westerly under
the developing ridge. Return moisture combined with strong heating
by Sunday may be enough to pop more orographic summer-like convection
over the ridges where will carry isolated thunder mountains
Saturday, and chance pops Sunday afternoon. This per the drier
ECMWF/CMC vs. the wetter GFS that has weaker ridging aloft
through the weekend.
Otherwise after a cool start to Thursday, will see a steady
increase in temperatures through the weekend as heights rise and
850 mb warming kicks in. Could even be close to 90 east of the
Blue Ridge by the end of the weekend, but not much humidity
until the very end of the period.
&&
.AVIATION /04Z MONDAY THROUGH FRIDAY/...
As of 800 PM EDT Sunday...
Main line of showers and thunderstorms is currently passing
east across KDAN, and will exit the area to the east by 13/02Z,
leaving lingering shower activity across the area through the
early morning hours of Monday. Models hinting at high pressure
over the DelMarVA nudging southward across the area overnight,
shifting winds east northeasterly and bringing ceilings in the
MVFR/IFR range, though not entirely confident how far the cold
front/leading edge of this weak high pressure will make it into
the area.
After daybreak Monday, a stronger cold front will pass east across
the central Appalachians, resulting in a westerly wind shift
areawide. May see an additional round of showers and possibly
thunderstorms develop just ahead of the front, primarily
affecting KDAN and an outside chance at KLYH. Downsloping
associated with the westerly flow will allow ceilings to
improve from east to west, with VFR conditions returning to much
of the area during late morning to early afternoon. Gusts
behind frontal passage will increase into the 20 to 25kt range
during the afternoon.
Confidence in the above portion of the aviation forecast is
moderate.
EXTENDED AVIATION DISCUSSION...
A few MVFR showers will continue in the western mountains
Monday evening. Then, they will taper off Monday night.
Tuesday will be VFR under high pressure. Isolated to scattered
MVFR showers are possible on Wednesday in the west. Drier air
will come in for Thursday.
Medium to High confidence in the extended portion of this
forecast.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...JH
NEAR TERM...AL/KK
SHORT TERM...JH
LONG TERM...JH
AVIATION...KK/NF