Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/16/16

AREA FORECAST DISCUSSION

NWS SAN FRANCISCO BAY AREA

1102 AM PDT MON MAR 14 2016

.SYNOPSIS...ISOLATED SHOWERS WILL CONTINUE THROUGH ABOUT MID
MORNING...WITH DRY CONDITIONS AND PARTIAL CLEARING EXPECTED FOR
THE REMAINDER OF THE DAY. HIGH PRESSURE IS FORECAST TO BUILD ALONG
THE WEST COAST OVER THE NEXT FEW DAYS...BRINGING DRY WEATHER AND A
WARMING TREND THROUGH THE WORK WEEK. RAIN CHANCES RETURN FOR THE
UPCOMING WEEKEND...BUT MAINLY ACROSS THE NORTH.

.DISCUSSION...AS OF 08:32 AM PDT MONDAY...FEW LINGERING SHOWERS
PERSIST OVER THE REGION THIS MORNING, MAINLY OVER THE SANTA CRUZ
MOUNTAINS. AS MENTIONED IN THE PREVIOUS DISCUSSION, EXPECTING THIS
ACTIVITY TO TAPER OFF THROUGH THE MORNING WITH MOSTLY DRY
CONDITIONS BY THIS AFTERNOON REGION-WIDE. IN ADDITION, SHOULD SEE
SOME BREAKS IN THE CLOUDS TODAY WITH TEMPERATURES WARMING
GENERALLY INTO THE 60S (UPPER 50S NEAR THE COAST). THE ONGOING
FORECAST REMAINS ON TRACK AND NO UPDATES ARE NEEDED AT THIS TIME.

.PREV DISCUSSION...AS OF 3:15 AM PDT MONDAY...KMUX RADAR SHOWS
ISOLATED LIGHT SHOWERS CONTINUING EARLY THIS MORNING...MAINLY
SOUTH OF THE GOLDEN GATE...AS THE FINAL IN A SERIES OF STORM
SYSTEMS EXITS TO THE EAST. RAINFALL AMOUNTS OVERNIGHT HAVE MOSTLY
BEEN LESS THAN A QUARTER OF AN INCH...EXCEPT UP TO A HALF INCH IN
THE SANTA CRUZ MOUNTAINS AND LOCALLY UP TO AN INCH IN THE SANTA
LUCIA RANGE OF MONTEREY COUNTY. CONSIDERABLE LOW LEVEL MOISTURE
HAS RESULTED IN PATCHY FOG WHICH IS EXPECTED TO LINGER THROUGH MID
MORNING.

THE LATEST HRRR MODEL SHOWS ISOLATED SHOWER ACTIVITY GRADUALLY
TAPERING OFF THROUGH SUNRISE...WITH JUST A FEW SHOWERS LINGERING
UNTIL MID MORNING. DRY WEATHER IS EXPECTED FOR THE REMAINDER OF
THE DAY ALONG WITH PARTIAL CLEARING AS A DRIER AIRMASS FILTERS IN
FROM THE NORTHWEST. HOWEVER...THERE WILL PROBABLY BE ENOUGH
RESIDUAL LOW LEVEL MOISTURE REMAINING FOR PATCHY FOG AND LOW
CLOUDS TO FORM TONIGHT. WHERE SKIES REMAIN CLEAR IN THE INLAND
VALLEYS...OVERNIGHT LOWS TONIGHT ARE EXPECTED TO DROP INTO THE
UPPER 30S.

THE MODELS HAVE BEEN CONSISTENT IN BUILDING AN UPPER RIDGE NEAR
THE WEST COAST THROUGH THURSDAY...AND ALSO DEVELOPING LIGHT
OFFSHORE FLOW BY MIDWEEK. THESE DEVELOPMENTS WILL RESULT IN DRY
WEATHER THROUGH THE WORK WEEK...ALONG WITH A WARMING TREND.
DAYTIME HIGHS WILL CLIMB INTO THE 70S IN MANY LOCATIONS BY
WEDNESDAY...WITH WIDESPREAD 70S FORECAST BY THURSDAY...ALONG WITH
A FEW LOWER 80S IN THE WARMER SOUTHERN INTERIOR LOCATIONS. DRY AND
BALMY CONDITIONS WILL CONTINUE INTO FRIDAY.

THE UPPER RIDGE AXIS IS FORECAST TO SHIFT TO OUR EAST BY SATURDAY
WHICH WILL RESULT IN SOMEWHAT COOLER CONDITIONS DURING THE
WEEKEND. ALSO...RAIN CHANCES WILL DEVELOP OVER THE WEEKEND AS A
BROAD UPPER TROUGH CENTERED IN THE GULF OF ALASKA EDGES CLOSER TO
THE WEST COAST. THE LONGER RANGE MODELS DON`T AGREE PARTICULARLY
WELL ON THE LOCATION AND TIMING OF RAINFALL DURING THE
WEEKEND...BUT THE GENERAL IDEA IS THAT MOST RAINFALL WILL MOVE
INLAND TO OUR NORTH AND THAT ONLY THE NORTHERN PORTION OF OUR
FORECAST AREA HAS A REASONABLE CHANCE OF GETTING WET.

.AVIATION...AS OF 10:58 AM PDT MONDAY...VFR TODAY WITH A HIGH
CLOUD DECK THAT WILL GRADUALLY DRY OUT AND DESCEND FROM 20K FT
DOWN TO 8K THROUGH THE NEXT 24-30 HOURS. LINGERING MOISTURE IN THE
LOW TO MID LEVELS ALSO SPAWNING FEW TO SCT CLOUDS A VARYING LEVELS
FROM 2-5K FT AGL. ADDITIONAL WEAK CUMULUS MAY DEVELOP INTO THE
AFTERNOON AND COULD BRIEFLY CAUSE FEW TO REBOUND TO SCT OR EVEN
BKN. CURRENTLY NOT ADDING ANY OVERNIGHT FOG TO TAF PACKAGE AS DEW
POINT DEPRESSION AND LOW LEVEL WINDS APPEAR JUST ENOUGH TO KEEP IT
AT BAY. THAT SAID... LOCALIZED POCKETS OF DENSE PATCHY FOG MAY BE
POSSIBLE IN SHELTERED AREAS WITH HIGHER DEW POINTS... COOLER
TEMPERATURES... AND LIGHTER WINDS.

VICINITY OF KSFO...PREDOMINATELY VFR WITH POSBL MVFR DEVELOPING AS
CUMULUS DEVELOPS INTO THE AFTERNOON. SCT CLOUD BASES COULD TURN TO
BKN AS DIURNAL HEATING/CONVECTION PICKS UP. WINDS GENERALLY OUT
OF THE WEST THIS AFTERNOON WITH A FEW SPORADIC GUSTS TO AROUND
20KT POSBL.

CONFIDENCE IS HIGH.

KSFO BRIDGE APPROACH...SIMILAR AS KSFO.

MONTEREY BAY AREA TERMINALS...PREDOMINATELY VFR WITH LIGHT ONSHORE
FLOW. A FEW GUSTS INTO THE AFTERNOON TO 15KT. AFTERNOON HEATING
MAY LEAD TO THICKENING CLOUDS AOA 2500-3500 FT RESULTING IN BRIEF
MVFR CIGS.

CONFIDENCE IS MODERATE.

.MARINE...AS OF 10:51 AM PDT MONDAY...NORTHERLY WINDS WILL
STRENGTHEN TODAY AND THROUGH MIDWEEK AS HIGH PRESSURE BUILDS
OFFSHORE. SQUARED SEAS WILL BE A THREAT IN ADDITION THE THE WINDS.
MODERATE SEAS WITH LARGE BREAKING WAVES ARE EXPECTED
TODAY...HOWEVER SEAS WILL DECREASE AS WE MOVE INTO THE AFTERNOON
AND EVENING HOURS.

.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ENTIRE COASTLINE UNTIL 3 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 11 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 11 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 11 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 11 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 3 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM

PUBLIC FORECAST: RGASS
AVIATION: DRP
MARINE: DRP

VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO

AREA FORECAST DISCUSSION

NWS SAN FRANCISCO BAY AREA

837 AM PDT MON MAR 14 2016

.AVIATION...AS OF 4:35 AM PDT MONDAY...THE CURRENT IR SATELLITE
IMAGE IS SHOWING A MIX OF MID LEVEL AND HIGH CLOUDS PASSING OVER
THE AREA BEHIND A DEPARTING COLD FRONT. THERE SHOULD BE ENOUGH
ATMOSPHERIC MIXING THIS MORNING TO PREVENT ANY LOW CLOUDS OR FOG
FROM FORMING. EXPECTING MVFR TO VFR CONDITIONS TODAY WITH CUMULUS
CLOUDS DEVELOPING LATER THIS MORNING.

VICINITY OF KSFO...VFR CONDITIONS ARE EXPECTED TO PREVAIL TODAY WITH
SCT-BKN035 DEVELOPING LATER THIS MORNING WITH HEATING OF THE DAY
PRODUCING CUMULUS TYPE CLOUDS. WESTERLY WINDS ARE ANTICIPATED TO
REACH 15 KT THIS AFTERNOON WITH GUSTS TO 20 KT POSSIBLE.

CONFIDENCE IS HIGH.

KSFO BRIDGE APPROACH...SIMILAR AS KSFO.

MONTEREY BAY AREA TERMINALS...MVFR CIGS TO START THE DAY THIS
MORNING. HOWEVER...CONDITIONS ARE EXPECTED TO IMPROVE TO SCT-
BKN025 LATER THIS MORNING. WESTERLY WINDS ARE EXPECTED TO REACH 8
TO 10 KT THIS AFTERNOON WITH GUSTS TO 15 KT POSSIBLE.

CONFIDENCE IS MODERATE.

.MARINE...AS OF 2:51 AM PDT MONDAY...WESTERLY WINDS WILL BECOME
MORE NORTHWESTERLY TODAY AS COOL AIR FILLS IN BEHIND A DEPARTING
COLD FRONT. AS THE NORTHERLY SURFACE PRESSURE GRADIENT STRENGTHENS
EXPECT MODERATE GUSTY WINDS TO DEVELOP SOUTH OF POINT SUR.
NORTHERLY WINDS ARE EXPECTED TO PERSIST THROUGH AT LEAST MID WEEK.
MODERATE SEAS WITH LARGE BREAKING WAVES OCCURRING AT NEAR SHORE
REEFS AND SAND BARS ARE EXPECTED TODAY...HOWEVER SEAS WILL
DECREASE AS WE MOVE INTO THE AFTERNOON AND EVENING HOURS.

.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ENTIRE COAST FROM SONOMA COUNTY
TO MONTEREY COUNTY
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 11 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 11 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 11 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 11 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 3 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM

PUBLIC FORECAST: RGASS
AVIATION: LARRY
MARINE: LARRY

VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO

AREA FORECAST DISCUSSION

NWS SAN DIEGO CA

832 AM PDT MON MAR 14 2016

.SYNOPSIS... LOW PRESSURE MOVING INLAND THROUGH THE GREAT BASIN WILL
KEEP STRONG ONSHORE FLOW...A DEEP MARINE LAYER...AND SCATTERED LIGHT
SHOWERS THIS MORNING. BECOMING PARTLY CLOUDY THIS AFTERNOON...WITH
THE GUSTY WESTERLY WINDS IN THE MOUNTAINS AND DESERTS SLOWLY
DIMINISHING. HIGH PRESSURE ALOFT AND WEAK OFFSHORE FLOW WILL BRING
DRY AND WARMER DAYS FOR THE REMAINDER OF THE WEEK...WITH WELL ABOVE
AVERAGE DAYTIME TEMPERATURES INLAND. LATE IN THE WEEK...ONSHORE FLOW
WILL BRING SOME COOLING...HIGHER HUMIDITY...AND A RETURN OF MARINE
CLOUDS TO COASTAL AREAS.
.

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

AT 8 AM PDT...RADAR SHOWED SCATTERED LIGHT SHOWERS DRIFTING SE WEST
OF THE MTS. RAINFALL AMOUNTS HAVE BEEN MOSTLY UNDER ONE-TENTH OF AN
INCH...EXCEPT IN SPOTS ON AND NEAR THE COASTAL SLOPES OF THE SAN
BERNARDINO MTS WHERE AMOUNTS TO THREE-QUARTERS OF AN INCH HAVE BEEN
REPORTED. NO MIRAMAR SOUNDING WAS AVAILABLE AT 12Z. SURFACE PRESSURE
GRADIENTS WERE RUNNING 5-7 MBS ONSHORE FROM KSAN TO THE DESERTS.
STRONGEST WINDS WERE RUNNING 25 WITH GUSTS TO AROUND 45 MPH IN THE
ONSHORE WIND-PRONE AREAS OF THE MTS.

A WIND ADVISORY IS IN EFFECT FOR THE MOUNTAINS AND HIGH DESERT AREAS
THIS MORNING BUT EXPECT IT WILL BE DISCONTINUED OVER THE MTS ON
SCHEDULE AT 10 AM PDT. MOSTLY CLOUDY THIS MORNING WEST OF THE MTS
WITH A FEW SHOWERS GRADUALLY DIMINISHING...BECOMING PARTLY CLOUDY IN
THE AFTERNOON. MOSTLY SUNNY IN THE DESERTS.

BASED ON AVAILABLE MOS GUIDANCE AND HI RES MODELS...MORE CLOUDS ARE
EXPECTED TO FORM ALONG THE COAST OVERNIGHT WITH AN EDDY FORECAST TO
DEVELOP. MUCH OF THIS SHOULD CLEAR OUT QUICKLY AS THE SYNOPTIC
GRADIENT BECOMES MORE OFFSHORE. SOME LOCALLY GUSTY WINDS ARE LIKELY
TO DEVELOP BELOW THE CAJON AND MORONGO PASS AREAS TUE/WED
MORNINGS...BUT SHOULD NOT REACH ADVISORY CRITERIA.

MODELS SHOW A HIGH AMPLITUDE RIDGE FORMING ALONG AND JUST OFF THE
WEST COAST WED/THU. A WEAKNESS IN THE HEIGHT FIELD SHOWS UP AT
AROUND 30N JUST OFFSHORE. THIS SEEMS TO RESULT IN THE DEVELOPMENT OF
A COASTAL EDDY ON THE LOCAL WRFEMS AND THE 12Z NAM 12 RUN. THIS MAY
RESULT IN SOME CLOUDS/FOG AND COOLING ALONG THE COAST AS EARLY AS
THU...BUT INLAND...THE DAYS WILL REMAIN QUITE WARM INTO THE WEEKEND.

.AVIATION...

141530Z...COAST/VALLEYS...A MIX OF CLOUD BASSES BETWEEN 800 AND 3500
FT MSL WILL OCCUR THROUGH 19Z...WITH AREAS OF VIS TO 1 SM IN -SHRA.
ANY PERIODS IFR CONDITIONS AT THE COASTAL TAF SITES SHOULD BE BRIEF.
LOW CLOUD TOPS BETWEEN 3500 AND 4500 FT MSL THROUGH 19Z. -SHRA
SHOULD DISSIPATE AFTER 19Z...WITH FEW-BKN CLOUD BETWEEN 2000 AND
3500 FT MSL THEREAFTER THROUGH 00Z. BKN CIGS WILL LOWER TO 700-2000
FT MSL AFTER 04Z AND BE FOCUSED WITHIN 25 SM OF THE COAST. A PERIOD
OF IFR CONDITIONS IS POSSIBLE AT KCRQ AFTER 04Z TUESDAY. CONFIDENCE
IN THE CIGS AFTER 04Z IS LOW TO MODERATE.

MOUNTAINS/DESERTS...BKN-OVC...VIS OF 1 SM OR LESS AND -SHRA WILL
CONTINUE ALONG THE COASTAL SLOPES THROUGH 21Z...WITH SKC-SCT
DEVELOPING AFTER 21Z. ELSEWHERE FEW-SCT AOA FL200 WILL PREVAIL
THROUGH 18Z TUESDAY. ONGOING AREAS OF WESTERLY WINDS AT 20 TO 25 KT
WITH GUSTS 40 KT WILL PRODUCE WEAK TO MODERATE UDDFS AND LLWS OVER
AND EAST OF THE MTNS THROUGH 00Z.

.MARINE...

830 AM...BREEZY WEST NORTHWEST WINDS AT 10 TO 18 KT WILL OCCUR
THROUGH THIS EVENING...ESPECIALLY OVER THE OUTER WATERS.
PREDOMINANTLY WINDS OF 10 KT OR LESS AND SWELL LESS THAN 5 FT
TUESDAY THROUGH FRIDAY.

.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WIND ADVISORY UNTIL 10 AM PDT THIS MORNING FOR RIVERSIDE COUNTY
MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS-SAN DIEGO COUNTY
DESERTS-SAN DIEGO COUNTY MOUNTAINS-SAN GORGONIO PASS NEAR
BANNING.

WIND ADVISORY UNTIL 6 PM PDT THIS EVENING FOR APPLE AND LUCERNE
VALLEYS.

PZ...NONE.
&&

PUBLIC...JAD
AVIATION/MARINE/BEACHES...ALBRIGHT

Area Forecast Discussion...UPDATED
National Weather Service Reno NV
811 AM PDT MON MAR 14 2016

.UPDATE...

Winds remain rather robust across the region this morning. Mammoth
Airport gusting to 62 mph, nearly the same at Five Mile Flat in
Storey County, and earlier we had 120 mph along the Sierra Crest
near Tahoe. Latest HRRR guidance has winds peaking over next few
hours then gradually subsiding by late afternoon as flow aloft
turns NW, lessens, and pressure gradient relaxes.

I`ll extend the wind advisories for Lovelock/Fallon/Mono Co areas
until 2 PM. Will also post a Lake Wind Advisory for Tahoe until 8
PM due to ongoing strong winds (40-45 mph on buoys) with rough
waters likely through the day today. Winds along the Sierra Front
will see gusts 40-55 mph, mainly in the wind prone areas and
foothills, so not widespread enough to warrant an advisory. -Chris

.PREVIOUS DISCUSSION... /Issued 333 AM PDT MON MAR 14 2016/

SYNOPSIS...

Rain and snow showers will diminish this morning as the winter storm
departs the region. Gusty winds continue today but will diminish by
late afternoon and evening. Quieter weather will return this week as
high pressure builds across the West and provides drier and warmer
conditions to the region.

SHORT TERM...

The last push of moisture is currently working its way across the
Sierra Interstate 80 corridor with lighter snowfall to south over
Mono County. Snow levels remained high overnight which produced a
rain/snow mix near the Lake Tahoe elevation and limited snow
accumulation. Currently snow levels remain around 6500-7000 feet
through the Tahoe Basin and 5500-6000 feet farther north through
Lassen County. Still looking for a few additional inches of
accumulation mainly above 7000 feet through the morning, but the
bulk of the precipitation has already fallen and have cancelled
the Winter Storm Warnings and Winter Weather Advisories. Snow
levels will slowly fall through the morning which should return a
rain/snow mix at lake level.

Some lingering showers will prevail through the afternoon but
precipitation amounts will be light with little additional impacts
expected through the afternoon. Winds will remain breezy today as a
west gradient develops behind the storm today. Wind Advisories will
remain in place over Mono and Mineral Counties and also the western
Nevada Basin and Range this morning with diminishing winds by this
evening. Choppy and hazardous boating conditions are expected for
Pyramid Lake and have posted a Lake Wind Advisory through the
afternoon.

After this system passes, we will return to a quieter and drier
weather pattern as a ridge of high pressure amplifies over the
eastern Pacific and west coast. High temperatures will warm a few
degrees above seasonal averages with upper 50s to low 60s possible
across western Nevada by mid-week. Overnight temperatures will be
chilly with freezing temperatures possible Tuesday and again
Wednesday morning. Lows in the 20s can be expected for Sierra
valleys through mid-week. Fuentes

LONG TERM...Thursday through Sunday...

High pressure continues to develop Thursday with the ridge axis west
of the Sierra. Model simulations show the ridge axis shifting
eastward to over the Sierra by Friday or Saturday. This pattern will
likely provide dry conditions, near average temperatures and
generally light NE-E winds for western NV and the eastern Sierra
through Friday and possibly through Saturday as well. However,
forecast confidence is lower starting Saturday regarding the
evolution of the ridge. It`s possible the ridge will weaken and
shift eastward Saturday or Sunday, which could lead to increasing
moisture streaming off the Pacific along with some potential for
valley rain and mountain snow showers for the second half of the
weekend. JCM

AVIATION...

Strong wind gusts 60-80 kts will continue across Sierra ridges
through this morning before slowly diminishing this afternoon.
These conditions will create moderate to severe turbulence in the
lee of the Sierra today. Terminals in the eastern Sierra and
western NV should expect wind gusts 25-40 kts today with a
decreasing trend during the afternoon. There is a chance for
occasional stronger gusts 45-55 kts in Mono/Mineral counties
including KMMH mainly through the morning hours.

Precipitation has tapered off to showers but mountain obscuration
along with brief MVFR or possibly IFR conditions remain possible at
Sierra terminals through this morning. VFR conditions are expected
to prevail across the area by afternoon. JCM

.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 2 PM this afternoon to 8 PM PDT this
evening for Pyramid Lake in NVZ004.

Wind Advisory until 2 PM PDT this afternoon NVZ001-004.

Lake Wind Advisory until 8 PM PDT this evening for Lake Tahoe in
NVZ002.

CA...Wind Advisory until 2 PM PDT this afternoon CAZ073.

Lake Wind Advisory until 8 PM PDT this evening for Lake Tahoe in
CAZ072.

For more information from the National Weather Service visit...
http://weather.gov/reno

AREA FORECAST DISCUSSION

NWS SAN FRANCISCO BAY AREA

436 AM PDT MON MAR 14 2016

.DISCUSSION...AS OF 3:15 AM PDT MONDAY...KMUX RADAR SHOWS ISOLATED
LIGHT SHOWERS CONTINUING EARLY THIS MORNING...MAINLY SOUTH OF THE
GOLDEN GATE...AS THE FINAL IN A SERIES OF STORM SYSTEMS EXITS TO
THE EAST. RAINFALL AMOUNTS OVERNIGHT HAVE MOSTLY BEEN LESS THAN A
QUARTER OF AN INCH...EXCEPT UP TO A HALF INCH IN THE SANTA CRUZ
MOUNTAINS AND LOCALLY UP TO AN INCH IN THE SANTA LUCIA RANGE OF
MONTEREY COUNTY. CONSIDERABLE LOW LEVEL MOISTURE HAS RESULTED IN
PATCHY FOG WHICH IS EXPECTED TO LINGER THROUGH MID MORNING.

CONFIDENCE IS HIGH.

KSFO BRIDGE APPROACH...SIMILAR AS KSFO.

CONFIDENCE IS MODERATE.

PUBLIC FORECAST: DYKEMA
AVIATION: LARRY
MARINE: LARRY

VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO

AREA FORECAST DISCUSSION

NWS SAN FRANCISCO BAY AREA

316 AM PDT MON MAR 14 2016

THE UPPER RIDGE AXIS IS FORECAST TO SHIFT TO OUR EAST BY SATURDAY
WHICH WILL RESULT IN SOMEWHAT COOLER CONDITIONS DURING THE
WEEKEND. ALSO...RAIN CHANCES WILL DEVELOP OVER THE WEEKEND AS A
BROAD UPPER TROUGH CENTERED IN THE GULF OF ALASKA EDGES CLOSER TO
THE WEST COAST. THE LONGER RANGE MODELS DONT AGREE PARTICULARLY
WELL ON THE LOCATION AND TIMING OF RAINFALL DURING THE
WEEKEND...BUT THE GENERAL IDEA IS THAT MOST RAINFALL WILL MOVE
INLAND TO OUR NORTH AND THAT ONLY THE NORTHERN PORTION OF OUR
FORECAST AREA HAS A REASONABLE CHANCE OF GETTING WET.

.AVIATION...AS OF 10:54 PM PDT SUNDAY...SHOWER COVERAGE DIMINISHES
OVERNIGHT. WIDESPREAD MVFR CIGS/VSBYS WITH AREAL COVERAGE OF IFR
CIGS/VSBYS GRADUALLY INCREASING. PATCHY FOG PERSISTS TONIGHT INTO
MONDAY MORNING. FOG POSSIBLE LATE MONDAY NIGHT INTO TUESDAY MORNING.

VICINITY OF SFO...WINDS BECOMING W LATE THIS EVENING THEN W-NW
OVERNIGHT. MVFR. SHOWERS GRADUALLY ENDING. LOW TO MODERATE
CONFIDENCE CIGS AND VSBYS FORECAST EARLY MONDAY MORNING.

KSFO BRIDGE APPROACH...SIMILAR AS KSFO.

MONTEREY BAY AREA TERMINALS...MVFR. SHOWERS GRADUALLY ENDING LATE
TONIGHT. MODERATE CONFIDENCE CIGS AND VSBYS FORECAST MONDAY MORNING.

PUBLIC FORECAST: DYKEMA
AVIATION: CANEPA
MARINE: LARRY

VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO

AREA FORECAST DISCUSSION

NWS MELBOURNE FL

448 AM EDT MON MAR 14 2016

.DISCUSSION...

TODAY...A MID LVL S/W TROUGH WILL MOVE EASTWARD ACROSS TN AND THE SE
STATES TODAY WITH MOST OF THE ASSOCIATED VORTICITY NORTH OF THE
REGION THOUGH A FEW MINOR IMPULSES ALOFT MAY AID IN TRIGGERING A FEW
LIGHTNING STORMS ACROSS E CENTRAL FL THIS AFTERNOON. DEEP LAYER WSW
FLOW IS FORECAST WITH CAPE VALUES SUFFICIENT FOR ISOLATED STORM
DEVELOPMENT. SHORT RANGE MODELS ARE SOMEWHAT AT ODDS ON CORRIDOR FOR
BEST CONVECTIVE DEVELOPMENT WITH 12KM NAM AND SPC WRF FAVORING NRN
PORTIONS OF THE E CENTRAL FL AND HRRR AND 00Z GFS FAVORING THE SRN
HALF. WILL KEEP A LOW THUNDER CHANCE EVERYWHERE FROM LATE MORNING
INTO THE AFTERNOON WITH CHANCES SHIFTING SOUTHWARD INTO THE LATE
AFTERNOON HOURS. GFS INDICATES SUBSTANTIAL DRYING IN THE H8-H7 LAYER
ACROSS NRN SECTIONS AFTER 2 PM LIKELY LIMITING CONVECTION FROM
ORLANDO NORTHWARD PAST MID AFTERNOON. ASIDE FROM THE LOW CONVECTIVE
CHANCES WELL ABOVE NORMAL TEMPS ARE EXPECTED WITH THE STRENGTHEING
LOW LVL SW FLOW INTO THE LATE MORNING AND AFTERNOON HOURS. HIGH
TEMPERATURES SHOULD REACH 85-87 ACROSS MUCH OF E CENTRAL FL.

TONIGHT...CONVECTION SHOULD MOVE EAST ACROSS THE ATLANTIC THIS
EVENING WITH PARTLY CLOUDY SKIES OVERNIGHT AND LOWS IN THE 60S.

TUE-WED...LOCAL ATMOSPHERE WILL EXPERIENCE GREATER EXTENT OF THE
ADVERTISED DEEP LAYER DRYING AS SHORTWAVE TROUGH MOVES SEAWARD OFF
THE MID-ATLANTIC COAST. UPPER FLOW FLATTENS SIGNALING A TEMPORARY
QUIET PERIOD. A SFC RIDGE OF HIGH PRESSURE WILL LOCATE OVER S FL TO
KEEP WINDS WITH A W COMPONENT. THIS WILL ALLOW DAYTIME TEMPS TO
REMAIN ON THE WARM SIDE INTO THE M/U80S. LIGHTER WINDS WED SHOULD
ALLOW FOR ECSB TO FORM WITH SOME INLAND PROGRESS TO DIAL WARMTH
DOWN ALONG THE COAST. MIN TEMPS M50S-L60S. DRY WITH NO
MENTIONABLE POPS.

THU-SUN...AN UNSETTLED PATTERN TO OFFER A MULTI-DAY CHANCE FOR
PRECIPITATION. S FL SFC RIDGE BEGINS TO YIELD GROUND TO SAGGING
FRONTAL BOUNDARY OVER N FL FOR THU. GATHERING MOISTURE OVER NC/NE
GULF OF MEXICO IN VICINITY OF THE NEARLY STATIONARY BOUNDARY ON FRI
WILL SPREAD E OVER PNSLA. SLIGHT CHANCE POPS N OF I-4 THU INCREASING
AND SPREADING SOUTH THROUGH FORECAST AREA FRI. A SHORTWAVE CARVES
INTO THE U.S. SOUTHEAST FOR THE WEEKEND INVIGORATING THE DEVELOPMENT
OF A SURFACE LOW OVER DIXIE AND DEEPENING AS IT TRANSITIONS TOWARD
THE MID-ATLANTIC. LOOK FOR FRONTAL PASSAGE DOWN THE PNSLA LATE IN
THE WEEKEND TO OFFER EVENTUAL SETTLEMENT. CHANCE POPS ALL ZONES SAT
AND SUN WITH THUNDER. MAX TEMPS L/M80S THU AND FRI THEN U70S-L80S
SAT/SUN DUE TO THICKENING CLOUDS. MIN TEMPS IN 60S.

.AVIATION...LOW BKN MVFR STRATUS WILL AFFECT NRN TERMINALS THROUGH
EARLY THIS MORNING. MAINLY VFR CIGS OUTSIDE OF ANY ISOLD SHRA/TSRA
THAT DEVELOP OVER E CENTRAL FL FROM LATE MORNING INTO MID AFTERNOON
AND MOVE EASTWARD TOWARD THE ATLC. SW WINDS 12-15 KNOTS AND GUSTY
15Z-22Z.

.MARINE... SW WINDS TO AROUND 15 KNOTS OFFSHORE WILL BUILD SEAS TO 3-
4 FT BEYOND 20NM OFFSHORE. SOME INCREASE IN THE GRADIENT WILL BRING
WINDS TO 15-20 KNOTS FOR A TIME ACROSS THE VOLUSIA COUNTY OFFSHORE
WATERS TONIGHT. ISOLATED CONVECTION WILL MOVE FROM THE MAINLAND INTO
THE ATLC LATER THIS AFTERNOON AND EVENING.

TUE-WED...FAVORABLE BOATING CONDITIONS ESPECIALLY FOR THE NEARSHORE
WATERS. WINDS AND SEAS WILL BE BELOW CAUTIONARY LEVELS. LITTLE TO NO
SHOWER ACTIVITY.

THU-FRI...A SAGGING FRONTAL BOUNDARY OVER N FL WILL INTRODUCE
ISOLATED SHOWERS NORTH OF CAPE CANAVERAL ON THU AND THEN SHOWERS
MENTIONED FOR ALL ZONES FRI. WINDS/SEAS REMAIN BELOW CAUTIONARY
LEVELS...BUT WEATHER PATTERN BECOMES UNSETTLED HEADING INTO THE
WEEKEND WITH THUNDER.

.FIRE WEATHER... BREEZY SW WINDS TODAY EXPECTED WITH MIN RHS AROUND
45 PCT ACROSS THE INTERIOR. TRANSPORT WINDS SW 20-25 KTS TODAY.
MIN RHS TO DROP TO NEAR 35 PERCENT FOR A FEW HOURS TUE AS SW WINDS
HELP MAINTAIN WARM CONDITIONS AND LOCAL ATMOSPHERE TEMPORARILY
DRIES OUT. RAIN CHANCES RE-ENTER THE FORECAST BY LATE WEEK WITH A
CHANCE FOR THUNDER.

.CLIMATE...WARM SOUTHWESTERLY FLOW ON MONDAY. MAY COME CLOSE TO
RECORD HIGHS FOR 14-MAR-16. RECORD HIGHS FOR MONDAY ARE AS FOLLOWS:

DAB...89 IN 1985.
MCO...90 IN 1917.
MLB...89 IN 1954.
VRB...89 IN 1980.

.PRELIMINARY POINT TEMPS/POPS...
DAB 85 62 84 60 / 20 10 0 0
MCO 87 65 88 62 / 20 10 0 0
MLB 86 66 86 57 / 30 10 0 0
VRB 86 64 85 58 / 30 10 0 0
LEE 85 63 86 62 / 20 10 0 0
SFB 86 66 87 61 / 20 10 0 0
ORL 87 66 87 63 / 20 10 0 0
FPR 86 63 87 56 / 30 10 0 0

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&

SHORT TERM...MRV
LONG TERM....DWS

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

814 PM EDT TUE MAR 15 2016

.SYNOPSIS...
HIGH PRESSURE WILL BE SOUTH AND EAST OF THE FORECAST
AREA THROUGH TONIGHT. A COLD FRONT WITH LITTLE MOISTURE WILL MOVE
INTO THE REGION WEDNESDAY. THE FRONT WILL BE STALLED JUST SOUTH OF
THE AREA WEDNESDAY NIGHT AND THURSDAY. INCREASED MOISTURE MAY
OCCUR OVER THE WEEKEND ASSOCIATED WITH LOW PRESSURE NEAR THE
SOUTHEAST COAST.

.NEAR TERM /THROUGH WEDNESDAY/...
DRY WEATHER WITH MUCH ABOVE NORMAL TEMPERATURES ARE FORECAST
THROUGH WEDNESDAY. THE MODELS DISPLAY FLAT UPPER RIDGING OVER THE
REGION THROUGH TONIGHT WITH SURFACE RIDGING EXTENDING FROM THE
ATLANTIC INTO THE GULF OF MEXICO. A DRY COLD FRONT WILL MOVE INTO
THE FORECAST AREA WEDNESDAY. THE NAM BUFKIT MOMENTUM TRANSFER TOOL
SUPPORTS WIND GUSTS AROUND 20 MPH WEDNESDAY. WE LEANED TOWARD THE
HIGHER MAXIMUM TEMPERATURE GUIDANCE BECAUSE OF RECENT TRENDS AND
WARMING AHEAD OF THE COLD FRONT. USED THE GUIDANCE CONSENSUS FOR
THE LOW TEMPERATURE FORECAST.

THE RECORD HIGH TEMPERATURE FOR CAE
MARCH 16: 88F SET IN 1921

THE RECORD HIGH TEMPERATURE FOR AGS
MARCH 16: 88F SET IN 1921

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
THE MODELS INDICATED DRY WEATHER WEDNESDAY NIGHT THROUGH THURSDAY
NIGHT WITH THE FRONTAL BOUNDARY STALLING TO OUR SOUTH AND HIGH
PRESSURE RIDGING INTO THE AREA FROM THE WEST. WESTERLY FLOW ALOFT
SHOULD HELP KEEP TEMPERATURES ABOVE NORMAL. THE NAM BUFKIT
MOMENTUM TRANSFER TOOL SUPPORTED WIND GUSTS NEAR 20 MPH THURSDAY.
FOLLOWED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST.

.LONG TERM /FRIDAY THROUGH TUESDAY/...
THE GFS AND ECMWF WERE CONSISTENT SHOWING DEEP MOISTURE
SUPPRESSED SOUTH OF THE FORECAST AREA FRIDAY. THERE REMAINED LOW
CONFIDENCE WITH THE FORECAST SATURDAY AND SUNDAY BECAUSE OF MODEL
INCONSISTENCY. COMPARED TO THE GFS THE ECMWF HAS DISPLAYED
DEVELOPING LOW PRESSURE CLOSER TO THE SOUTHEAST COAST WITH DEEP
MOISTURE IN THE FORECAST AREA. THE GFS ENSEMBLE GUIDANCE
INDICATED A HIGH SPREAD. THE GFS...ECMWF...AND EKD MOS HAD POPS
20 TO 70 PERCENT SATURDAY AND SUNDAY WITH THE ECMWF INDICATING
THE HIGHER VALUES. WE HAVE CONTINUED THE FORECAST OF CHANCE POPS
BOTH DAYS FOLLOWING AN AVERAGE OF THE MOS AND GFS ENSEMBLE MEAN.
THE MOS INDICATED BELOW NORMAL TEMPERATURES SUNDAY AND MONDAY.

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS EXPECTED DURING THE TAF PERIOD OUTSIDE OF POSSIBLE
STRATUS WEDNESDAY MORNING.

SMOKE...POSSIBLY FROM A PRESCRIBED BURN...MAY LINGER OVER CAE/CUB
THROUGH 01Z. SMOKE MAY LIMIT VISIBILITIES AT TIMES HOWEVER
PREVAILING VFR CONDITIONS ARE EXPECTED.

VFR CONDITIONS WILL CONTINUE THIS EVENING WITH DRY SURFACE HIGH
PRESSURE RIDGING INTO THE REGION. WINDS TONIGHT WILL BE GENERALLY
SOUTHWESTERLY AT 5 KNOTS OR LESS. A 35 KNOT LOW LEVEL JET SHOULD
PRECLUDE A FOG THREAT EARLY WEDNESDAY. THERE IS SOME DISAGREEMENT
BETWEEN THE NAM AND GFS MODEL GUIDANCE WHETHER LOW CLOUDS WILL
MOVE IN OVERNIGHT. HRRR DATA HAS BEEN CONSISTENT INDICATING
MVFR/IFR CEILINGS MOVING IN FROM SOUTHERN GA INTO THE CSRA NEAR
DAYBREAK. THIS ADDS CONFIDENCE IN AT LEAST MVFR CEILINGS AT
AGS/DNL EARLY WEDNESDAY MORNING.

WINDS WILL PICK UP OUT OF THE WEST WEDNESDAY MORNING TO AROUND 10
TO 15 KNOTS WITH GUSTS UP TO 20 KNOTS. THIS WILL HELP SCATTER OUT
THE LOW STRATUS BY LATE MORNING. A DRY COLD FRONT WILL MOVE
THROUGH THE TAF SITES NEAR THE END OF THE TAF PERIOD BRINGING
GUSTY NORTHWESTERLY WINDS.

EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED TUESDAY THROUGH SATURDAY.

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.

AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

154 PM EDT MON MAR 14 2016

.PREV DISCUSSION... /ISSUED 1102 AM EDT MON MAR 14 2016/

.UPDATE...
PULLED BACK POPS FARTHER NORTH INTO MIDDAY BASED ON TRENDS WITH
SHORTWAVE THOUGH OVERALL THOUGHT ON POSSIBLE THREATS HAS NOT
CHANGED AND SPC DID EXTEND THE MARGINAL RISK /5 PERCENT WIND...5
PERCENT HAIL/ INTO MUCH OF NORTH GA. MAIN COLD CORE AND TROUGH
AXIS IS STILL TO THE WEST THOUGH INITIAL FRONT WAVE OF DEVELOPMENT
HAS HAD A WANING TREND. RAP PROGGED MLCAPE STILL INDICATES NOSE OF
500 J/KG ADVECTING NE AHEAD OF WAVE SO EXPECTING SOME INITIATION
THIS AFTERNOON...THOUGH FAIRLY AMPLE CLOUD COVERAGE IS PRECEDING
THE WAVE WHICH COULD FURTHER SUPPRESS DAYTIME DESTABILIZATION.
CANNOT RULE OUT FOCI FOR POSSIBLE DEVELOPMENT FARTHER SOUTH INTO
CENTRAL GA WHERE MORNING CLOUD DECK EDGES COULD ENHANCE SFC
BAROCLINITY...BUT WOULD BE LESS JUXTAPOSED WITH UPPER DYNAMICS SO
HAVE STILL KEPT POPS MAINLY ACROSS NORTH GA. OTHERWISE MADE MINOR
ADJUSTMENTS AND PREVIOUS DISCUSSION FOLLOWS...

BAKER

PREV DISCUSSION... /ISSUED 625 AM EDT MON MAR 14 2016/

.SHORT TERM /TODAY THROUGH TUESDAY/...
LINE OF THUNDERSTORMS WORKING ITS WAY ACROSS NORTHERN MISSISSIPPI
EARLY THIS MORNING HAS SHOWN A SLOW WEAKENING TREND...AND THIS
SHOULD CONTINUE AS IT MOVES ACROSS NORTHERN ALABAMA TOWARD NORTH
GEORGIA THIS MORNING. MODELS CONTINUE TO GRADUALLY WEAKEN THE SHORT
WAVE DRIVING THESE STORMS AS IT PROGRESSES EAST...AND INSTABILITY
REMAINS MODEST ACROSS OUR AREA THROUGH THE DAY. AREA OF BETTER MID-
LEVEL LAPSE RATES IS FORECAST TO SHIFT INTO THE CAROLINAS AND LOW-
LEVEL SHEAR IS MODERATE AT BEST. A FEW STRONG STORMS WOULD NOT BE
IMPOSSIBLE ACROSS THE FAR NORTH LATE MORNING INTO THE AFTERNOON...
BUT SEVERE THREAT REMAINS LOW. CHANCE OF LINGERING SHOWERS QUICKLY
EXITS NORTHEAST GEORGIA BY EARLY IN THE EVENING. THE REMAINDER OF
THE SHORT TERM FORECAST PERIOD LOOKS DRY AND MILD AS UPPER-LEVEL
RIDGING TRANSITS THE REGION BEHIND THE SHORT WAVE TONIGHT AND
TUESDAY.

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MODELS IN GOOD AGREEMENT FOR THE FIRST PART OF THE LONG
TERM...HOWEVER THEY DIVERGE IN THEIR SOLUTION AFTER WEDNESDAY. THE
GFS BRINGS AMPLE MOISTURE ACROSS THE CWA WEDNESDAY NIGHT AND EARLY
THURSDAY AS A WEAK COLD FRONT MOVES ACROSS THE CWA WHILE THE
ECMWF AND CANADIAN KEEP IT MOSTLY DRY. THE FRONT STALL ACROSS THE
NORTHERN GULF COAST. A LOW DEVELOPS ALONG THE FRONT ACROSS THE
NORTHCENTRAL GULF AND MOVES NORTHEAST. HOWEVER ALL MODELS DIFFER
IN TIMING AND STRENGTH. WILL CONTINUE TO MAINTAIN CHANCE POPS
THROUGH THE WEEKEND.

.AVIATION...
18Z UPDATE...
LOW END VFR CIGS WITH PASSING SHORTWAVE DISTURBANCE AND MOSTLY
VCSH ACROSS NORTHERN SITES...POSSIBLY FLIRTING WITH KCSG THIS
AFTERNOON. BEST THUNDER CHANCES MAINLY JUST NORTH OF TAF SITES
THOUGH COULD BE A FEW HOURS OF ISOLATED -TSRA SO INCLUDED TEMPO
FOR KATL 20-22Z AND NEARBY SITES. OTHERWISE SOME POTENTIAL
CLEARING AFTER ABOUT 03-05Z THIS EVENING WITH LIGHT SW WINDS.
GUIDANCE INDICATING POTENTIAL FOR MVFR CIGS SNEAKING INTO SOUTHERN
SITES FOR EARLY MORNING WITH SOME REDUCED VSBYS...SO INCLUDED AT
LEAST SCT015 WITH 4SM BR FOR 09-14Z TUESDAY. SW WINDS BACK TO
7-10 KTS FOR TUESDAY AFTERNOON.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON INITIAL PRECIP/THUNDER POTENTIAL AND OVERNIGHT SOUTHERN
CIGS.
HIGH ON ALL ELSE.

BAKER

.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 54 83 58 / 40 30 0 0
ATLANTA 76 56 82 59 / 20 10 0 5
BLAIRSVILLE 70 50 78 52 / 60 30 0 5
CARTERSVILLE 75 52 83 55 / 50 10 0 10
COLUMBUS 81 56 84 57 / 10 5 0 5
GAINESVILLE 73 53 80 57 / 50 30 0 5
MACON 81 55 86 58 / 10 5 0 0
ROME 74 51 83 55 / 50 10 5 10
PEACHTREE CITY 77 52 84 57 / 20 10 0 5
VIDALIA 84 60 85 60 / 10 5 0 0

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...20/BAKER
LONG TERM....41
AVIATION...BAKER

AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

1102 AM EDT MON MAR 14 2016

BAKER

.PREV DISCUSSION... /ISSUED 625 AM EDT MON MAR 14 2016/

.AVIATION...
12Z UPDATE...

MVFR OR LOWER CEILINGS DEVELOPING BETWEEN 12Z AND 14Z. VFR
CONDITIONS RETURN MOST AREAS BY 18Z. WINDS SOUTHEAST TO SOUTHWEST
4KT OR LESS...BECOMING SOUTHWEST 7-10KT W/ GUSTS 15-20KT BY 14-16Z.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE NORTHERN HALF OF THE
FORECAST AREA BETWEEN 12Z AND 00Z. BETTER CHANCES REMAIN NORTH OF
THE TAF SITES...HOWEVER THE ATLANTA METRO TAF SITES AND KAHN MAY SEE
SCATTERED CONVECTION IN THE AREA BETWEEN 16Z AND 22Z.

//ATL CONFIDENCE...12Z UPDATE...

MEDIUM ON CEILINGS THROUGH EARLY AFTERNOON...HIGH ALL OTHER ELEMENTS.

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...20/BAKER
LONG TERM....41
AVIATION...20

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

219 AM EDT MON MAR 14 2016

.SYNOPSIS...
LOW PRESSURE WILL BE LIFTING NORTHEASTWARD FROM THE CENTRAL
MISSISSIPPI RIVER VALLEY INTO THE OHIO VALLEY THROUGH MONDAY.
PRESSURE TROUGHS ROTATING AROUND THE LOW WILL BE IN THE FORECAST
AREA MONDAY AFTERNOON AND EVENING. SURFACE HIGH PRESSURE WILL
EXTEND FROM THE ATLANTIC INTO THE GULF OF MEXICO THROUGH
WEDNESDAY.

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION SLOWLY MOVING ACROSS THE PIEDMONT AND NORTH MIDLANDS IN
AN AREA OF LOW LEVEL CONVERGENCE. CONVECTION MOVING TOWARD AIRMASS
THAT IS STILL SLIGHTLY UNSTABLE. HIGH RESOLUTION RAP MODEL KEEPS
SOME CONVECTION CROSSING THE NORTH MIDLANDS FOR THE NEXT SEVERAL
HOURS. HRRR MODEL ENDS ALL CONVECTION BY 06Z. SATELLITE
INDICATED CLOUD TOPS COOING SINCE 03Z. GIVEN THESE TRENDS WILL
KEEP CHANCE FOR CONVECTION ACROSS THE NORTH MIDLANDS THROUGH 06Z.

MOISTURE EXPECTED TO BE MAINLY SHALLOW OVERNIGHT. WITH DRY AIR
ALOFT AND DIMINISHING WINDS IN THE BOUNDARY LAYER FOG MAY DEVELOP.
OVERNIGHT LOWS AROUND 60 APPEAR ON TRACK. OVERNIGHT LOWS WILL BE
IN THE UPPER 50S TO LOWER 60S.

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
CONVERGENCE ASSOCIATED WITH A SURFACE PRESSURE TROUGH WILL OCCUR
MONDAY AFTERNOON AND EVENING. THE STRONGEST LIFT ASSOCIATED WITH A
DAMPENING H5 SHORTWAVE TROUGH WILL REMAIN NORTH OF THE FORECAST
AREA. HOWEVER...THE MODELS STILL DEPICT VERY COLD H5 TEMPERATURES
OF -17 TO -18 C. MOISTURE WILL BE LIMITED ESPECIALLY IN THE SOUTH
PART OF THE FORECAST AREA BECAUSE OF DRYING BEHIND THE LEAD MID-
LEVEL SHORTWAVE TROUGH THAT LIFTED NORTHEAST OF THE AREA SUNDAY.
THEREFORE...THUNDERSTORM COVERAGE SHOULD BE LIMITED. THE NAM AND
GFS MOS HAVE POPS 40 TO 50 PERCENT NORTH TO LESS THAN 20 PERCENT
SOUTH. THE NAM SHOWS SURFACE-BASED LI/S -7 TO -10 WITH THE
GREATEST INSTABILITY IN THE NORTH PART WITH COLDER TEMPERATURES
ALOFT. THE STRONG INSTABILITY SUPPORTS POSSIBLE SEVERE
THUNDERSTORMS. THE PRIMARY THREATS WILL BE DAMAGING HAIL AND WIND.

THE TROUGH WILL HAVE LIFTED NORTHEAST OF THE FORECAST AREA BY
LATE MONDAY NIGHT WITH FURTHER DRYING. THE MODELS DISPLAY FLAT
UPPER RIDGING OVER THE REGION WITH SURFACE HIGH PRESSURE EXTENDING
FROM THE ATLANTIC INTO THE GULF OF MEXICO. IT SHOULD BE DRY WITH
ABOVE NORMAL TEMPERATURES.

WE USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST MONDAY
THROUGH TUESDAY.

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE GFS AND ECMWF DISPLAY A COLD FRONT WILL LITTLE MOISTURE
APPROACHING TUESDAY NIGHT. THE FRONT IS FORECAST TO STALL IN THE
FORECAST AREA WEDNESDAY WITH A GENERAL INCREASE IN MOISTURE
THROUGH FRIDAY. DEEP MOISTURE MAY OCCUR BY SATURDAY WITH BACKING
MID-LEVEL HEIGHTS. THE GFS...ECMWF...AND EKD MOS HAVE POPS LESS
THAN 20 PERCENT THROUGH WEDNESDAY...AND 30 TO 70 PERCENT THURSDAY
THROUGH SATURDAY. THE ECMWF POPS WERE HIGHEST CENTERED FRIDAY
AND SATURDAY. MUCH ABOVE NORMAL TEMPERATURES SHOULD CONTINUE
THROUGH THURSDAY...BUT LOWER TO ABOUT NORMAL FOR FRIDAY AND
SATURDAY WITH CLOUDINESS AND POSSIBLE RAIN AS INDICATED BY THE
MOS.

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
HIGH CONFIDENCE IN MVFR/IFR CIGS EARLY IN THE FORECAST PERIOD
FOLLOWED BY IMPROVING CONDITIONS LATE MORNING.

SOME EVENING CONVECTION ALONG A WEAK SURFACE TROUGH HAS DISSIPATED
ACROSS THE WESTERN AND NORTHERN MIDLANDS SO NO RAINFALL IS
EXPECTED TO IMPACT THE TERMINALS OVERNIGHT. HOWEVER...SATELLITE
IMAGERY SHOWS WIDESPREAD STRATUS DEVELOPMENT OCCURRING ACROSS
SOUTHEAST GEORGIA AND MUCH OF CENTRAL AND EASTERN SOUTH CAROLINA
WHICH IS EXPECTED TO CONTINUE AND EXPAND THROUGH THE PREDAWN
HOURS. LOW MVFR AND IFR CIGS EXPECTED ALL TERMINALS FROM 07Z-13Z
WITH GRADUAL IMPROVEMENT THROUGH 15Z BACK TO VFR CONDITIONS. WINDS
WILL PICK UP FROM THE SOUTHWEST AFTER 16Z AT 10 TO 15 KNOTS WITH
SOME GUSTS OVER 20 KNOTS THROUGH THE AFTERNOON.

SHORTWAVE ENERGY MOVING INTO THE REGION LATE AFTERNOON MONDAY WILL
COMBINE WITH INSTABILITY AND BRING INCREASED CHANCES OF ISOLATED
CONVECTION WITH SOME STORMS BEING STRONG BUT MOST OF THE THIS
ACTIVITY IS EXPECTED TO BE NORTH OF THE TERMINALS AND NOT
INCLUDING IN THIS FORECAST.

EXTENDED AVIATION OUTLOOK...SOME MVFR RESTRICTIONS DUE TO EARLY
MORNING FOG POSSIBLE TUESDAY MORNING.

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

1215 AM EDT MON MAR 14 2016

.NEAR TERM /UNTIL 8 AM MONDAY MORNING/...
CONVECTION SLOWLY MOVING ACROSS THE PIEDMONT AND NORTH MIDLANDS IN
AN AREA OF LOW LEVEL CONVERGENCE. CONVECTION MOVING TOWARD AIRMASS
THAT IS STILL SLIGHTLY UNSTABLE. HIGH RESOLUTION RAP MODEL KEEPS
SOME CONVECTION CROSSING THE NORTH MIDLANDS FOR THE NEXT SEVERAL
HOURS. HRRR MODEL ENDS ALL CONVECTION BY 06Z. SATELLITE
INDICATED CLOUD TOPS COOING SINCE 03Z. GIVEN THESE TRENDS WILL
KEEP CHANCE FOR CONVECTION ACROSS THE NORTH MIDLANDS THROUGH 06Z.

.SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY/...
CONVERGENCE ASSOCIATED WITH A SURFACE PRESSURE TROUGH WILL OCCUR
MONDAY AFTERNOON AND EVENING. THE STRONGEST LIFT ASSOCIATED WITH A
DAMPENING H5 SHORTWAVE TROUGH WILL REMAIN NORTH OF THE FORECAST
AREA. HOWEVER...THE MODELS STILL DEPICT VERY COLD H5 TEMPERATURES
OF -17 TO -18 C. MOISTURE WILL BE LIMITED ESPECIALLY IN THE SOUTH
PART OF THE FORECAST AREA BECAUSE OF DRYING BEHIND THE LEAD MID-
LEVEL SHORTWAVE TROUGH THAT LIFTED NORTHEAST OF THE AREA SUNDAY.
THEREFORE...THUNDERSTORM COVERAGE SHOULD BE LIMITED. THE NAM AND
GFS MOS HAVE POPS 40 TO 50 PERCENT NORTH TO LESS THAN 20 PERCENT
SOUTH. THE NAM SHOWS SURFACE-BASED LI/S -7 TO -10 WITH THE
GREATEST INSTABILITY IN THE NORTH PART WITH COLDER TEMPERATURES
ALOFT. THE STRONG INSTABILITY SUPPORTS POSSIBLE SEVERE
THUNDERSTORMS. THE PRIMARY THREATS WILL BE DAMAGING HAIL AND WIND.

WE USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST MONDAY
THROUGH TUESDAY.

.AVIATION /04Z MONDAY THROUGH FRIDAY/...
RESTRICTIONS POSSIBLE IN EARLY MORNING FOG/STRATUS AND LATER TODAY
IN AFTERNOON CONVECTION.

CONCERN FOCUSES ON EARLY MORNING FOG...AND WITH AVAILABLE
MOISTURE ON THE GROUND EXPECT PATCHY FOG TO DEVELOP. EXPECT
MVFR/POSSIBLE IFR VSBYS FROM THE EARLY MORNING HOURS THROUGH
DAYBREAK...WITH FOG MIXING OUT BY AROUND 13Z. AFTERNOON CONVECTION
POSSIBLE AFTER 20Z BUT DUE TO AREAL AND TIMING ISSUES...WILL NOT
MENTION AT ANY OF THE TAF SITES AT THIS TIME.

EXTENDED AVIATION OUTLOOK...LOW PRESSURE MOVING NORTH OF THE
REGION WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA
MONDAY EVENING. SOME MVFR RESTRICTIONS DUE TO EARLY MORNING FOG
TUESDAY MORNING.

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.

AREA FORECAST DISCUSSION

National Weather Service Lincoln IL

820 PM CDT TUE MAR 15 2016

.UPDATE...
ISSUED AT 815 PM CDT TUE MAR 15 2016

Deepening surface low now over west central Illinois this evening
with the warm front extending east southeast from the low over
central to southeast Illinois. Dew points have risen to around
60 degrees across our area this evening ahead of the strong low.
Strongest storms will continue to edge east northeast ahead of
the surface low for the rest of the evening. Tornado watch number
44 has been extended to 10 pm CDT and we may need to add some
counties further east over the next few hours as well. Updated
zone forecast with the new watch extension time will be out
in the next 10-15 minutes.

.SHORT TERM...(Tonight)
ISSUED AT 312 PM CDT TUE MAR 15 2016

19z/2pm surface analysis shows a 997mb low over northeast Missouri,
with a warm front extending E/SE across south-central Illinois.
Despite the presence of this forcing, convection has not yet
materialized across Missouri or Illinois as the atmosphere remains
capped. The short-wave trough that will eventually approach from
the west and break the cap is still well to the west across western
Kansas/Nebraska, so think cap will hold firm through the remainder
of the afternoon. HRRR has been consistently showing scattered
thunderstorms developing along the trailing cold front across
eastern Missouri after 21z/4pm...with the activity then tracking
E/NE into central Illinois this evening. 4km WRF-NMM has similar
timing, and both high-res models suggest the storms will quickly
shift out of the KILX CWA by midnight. Given strong directional low-
level wind shear in the vicinity of the warm front, the main mode of
any convection that develops later today will be supercellular. As
such, damaging wind gusts and large hail remain the primary
threats...although a few tornadoes will also be possible mainly
along and northwest of the I-55 corridor. Have therefore included
likely PoPs and mentioned severe weather across the western half of
the CWA this evening accordingly. Any convection that fires will
rapidly push eastward out of the area by midnight, with only a few
lingering rain showers across the NW from the Peoria area northward
after midnight. Once the storms pass, strong/gusty southwesterly
winds will develop, with forecast soundings and numeric guidance
suggesting gusts of 30-35 mph. Overnight lows will drop into the
middle to upper 40s.

.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 312 PM CDT TUE MAR 15 2016

Deepening surface low pressure forecast to push into central
Wisconsin by 12z Wednesday with a tight pressure gradient over most
of the forecast area during the day. Forecast soundings showing 40-
45 kts just off the surface tomorrow mid morning through the
afternoon hours so wind gusts of 35 to 45 mph look likely over
most of the area, except south of the Interstate 70 corridor. As
a result, a wind advisory will be issued for a good portion of
the forecast area for tomorrow. Areas north of I-74 will get close
to some warning criteria winds, especially if the wrap around
moisture/clouds stay to our north like most of the models suggest.
Despite the passage of the cold front this evening, temperatures
will be mild again on Wednesday, although not as warm as today.
Look for highs to climb into the 60s most areas.

The strong surface low will begin to fill across the lower Great
Lakes on Thursday as upper level energy is transferred over to the
East Coast. This will result in an elongated surface trof from the
new low off New England west through the southern Great Lakes.
This feature will gradually slide south bringing a more extensive
cloud band south with it and the threat for some light precip
starting on Friday night and continuing on and off into Saturday
night. We may see a mix of rain and snow across our north Friday
night into early Saturday morning, and possibly again late
Saturday night into Sunday. No accumulations are expected with any
snow that does occur across our north.

The upper trof will gradually work its way southeast across the
Great Lakes on Sunday and Monday with rather cool temperatures
prevailing, at least compared to what we have had over the past
couple of days. However, with the trof being more progressive, the
cool down will not last long as most medium range models suggest
the trof will shift off to our east by early next week with more
of a zonal flow developing over the Midwest resulting in a gradual
moderating trend through the middle of next week.

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 642 PM CDT TUE MAR 15 2016

Main aviation forecast concern continues to be developing convection
this evening. Based on latest radar trends and HRRR run, have
included a TEMPO group for thunder and MVFR ceilings at KPIA/KSPI
between 00z and 02z...then further east to KBMI/KDEC between 01z
and 03z. Given uncertainties in areal coverage further east, have
only mentioned VCTS at KCMI after 02z. Once the storms pass, NAM
forecast soundings suggest a period of MVFR ceilings before skies
clear overnight into Wednesday morning. Winds will initially be
from the south-southeast with gusts to around 25kt this
evening, then will veer to the west-southwest after frontal
passage this evening. As the pressure gradient tightens, very
strong W/SW winds gusting to between 30 and 35kt will be likely on
Wednesday.

.ILX Watches/Warnings/Advisories...
Wind Advisory from 7 AM to 8 PM CDT Wednesday for ILZ027>031-
036>038-040>057-061>063.

UPDATE...Smith
SHORT TERM...Barnes
LONG TERM...Smith
AVIATION...Barnes

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

744 PM CDT TUE MAR 15 2016

.MESOSCALE DISCUSSION...
742 PM CDT

CONVECTIVE INITIATION HAD BEGUN LATE THIS AFTERNOON ACROSS FAR
NORTHEAST MISSOURI TO NEAR QUINCY...AND HAS SINCE BECOME ORIENTED
FROM THE QUAD-CITIES STRETCHING SOUTH TO PIKE COUNTY ILLINOIS.
ACROSS NORTHEAST ILLINOIS THE LAKE INFLUENCE WILL LIKELY MAINTAIN
A STABLE ENVIRONMENT FOR A FEW MORE HOURS...AND COULD LINGER
LONGER INTO THE EVENING. 18Z SOUNDINGS HAD SUGGESTED A MODEST LID
ON DEVELOPMENT ACROSS CENTRAL IL...HOWEVER HI-RES GUIDANCE
SUGGESTED THIS WARM LAYER ALOFT WOULD STEADILY DISSOLVE AND THAT
APPEARS TO BE THE CASE AT 00Z. 0- 3KM SHEAR REMAINS SOLID BOTH
WITH DIRECTIONAL/SPEED COMPONENTS...HOWEVER AS WE PROGRESS INTO
THE EVENING HOURS THE FOCUS BECOMES THE FORCING WITHIN THE SYSTEM
AND DEPTH OF LOW-LEVEL MOISTURE. THE LOW CONTINUES TO
DEVELOP...AND IS EXPECTED TO SEE STEADY DEEPENING TO THE SFC
FEATURE OVER THE NEXT 3-5 HOURS...WITH LAPSE RATES REMAINING
STEEP.

A SUPERCELL THAT HAD EXHIBITED SOME ROATATION EARLIER THIS EVENING
IN THE HANCOCK/HENDERSON/WARREN IL COUNTIES WAS LIFTING
EAST/NORTHEAST...AND MAY BE ROOTED ALONG THE NORTHERN PERIPHERY OF
THE 330 THETA-E ADVECTION CONTOUR...WHICH LINES UP WITHIN THE
AREA OF DEWPOINTS AROUND 60 DEGREES. THIS MAY END UP FEEDING
ALONG THE HIGHER DEW POINT ENVIRONMENT...WHICH WOULD FAVOR A SOUTH
OF GRUNDY/GARY LINE.

SHEAR REMAINS PRONOUNCED FURTHER NORTH OF THIS FEATURE...WHICH COULD
CONTINUE TO SUPPORT THE POSSIBILITY OF ROTATING UPDRAFTS ALONG THE
CURRENT TORNADO WATCH COUNTIES ALONG AND WEST OF WINNEBAGO TO
LIVINGSTON COUNTIES. FURTHER EAST OF THIS AREA THE AS THE LOW LIFTS
NORTHEAST...THE SHEAR WITHIN THE LOWEST 0-3KM ENVIRONMENT REMAINS
GOOD ALTHOUGH EXPECTING CONVECTION TO BE TRANSITIONING TOWARDS
ELEVATED. DESPITE THE EASTERLY LOW LEVEL FLOW NORTH OF I-80 AND EAST
OF THE CURRENT TORNADO WATCH...THE POTENTIAL WILL REMAIN FOR LARGE
HAIL INTO THE LATE EVENING HOURS. MLCAPE WILL CONTINUE TO HOVER IN
THE 600-800J/KG RANGE OVER NORTHEAST IL...WITH RAPIDLY TURNING
WITHIN THE WIND FIELDS ALOFT. HI-RES CONVECTIVE MODELS CONTINUE TO
SUPPORT THIS SOLUTION...BRINGING CONVECTION NORTHEAST ACROSS THE
CHICAGO METRO AREA CLOSER TO 3-6Z TIMEFRAME.

BEACHLER

.SHORT TERM...
320 PM CDT

TONIGHT THROUGH WEDNESDAY NIGHT...

PRIMARY FORECAST FOCUS IS WITH SEVERE WEATHER POTENTIAL THROUGH
THIS EVENING...AND VERY WINDY CONDITIONS DEVELOPING LATER TONIGHT
AND CONTINUING THROUGH WEDNESDAY NIGHT.

SFC LOW PRESSURE WAS DEEPENING ACROSS NORTHEASTERN MISSOURI EARLY
THIS AFTERNOON...IN RESPONSE TO A VIGOROUS MID-LEVEL SHORT WAVE
PROPAGATING ACROSS EASTERN KANSAS AND INTO THE MID-MISSOURI RIVER
VALLEY PER GOES WATER VAPOR IMAGERY. SOUTH-SOUTHEAST LOW LEVEL
RETURN FLOW PRODUCING IMPRESSIVE WARM SECTOR AIR MASS FOR MID-
MARCH... CHARACTERIZED BY AIR TEMPS IN THE LOW-MID 70S AND SURFACE
DEW POINTS OF 55-60 INTO CENTRAL IL/WEST CENTRAL IN INCLUDING
SOUTHERN COUNTIES OF THE WFO LOT CWA. WHILE SURFACE FLOW IS BACKED
TO THE SOUTHEAST ACROSS THE AREA...THE EFFECTIVE SURFACE WARM
FRONT APPEARS TO BE APPROXIMATELY NEAR A GALESBURG-PONTIAC-
LAFAYETTE LINE. CONSIDERABLE SUNSHINE WAS HELPING TO DESTABILIZE
THE AIR MASS ACROSS THE MISSISSIPPI VALLEY AND CENTRAL IL...WITH
SPC RAP ANALYSIS INDICATING MLCAPES INCREASING TO 1000-1500 J/KG
WITH CIN WEAKENING TO 100 J/KG OR LESS. DYNAMICS ARE BECOMING MORE
FAVORABLE FOR SEVERE CONVECTION AS WELL WITH APPROACH OF STRONG
MID-LEVEL WAVE...WITH 60 KT EFFECTIVE DEEP LAYER BULK SHEAR AND
0-3 KM STORM RELATIVE HELICITY OF 200-300 M2S2 IN THE VICINITY OF
THE WARM FRONTAL BOUNDARY. VISIBLE SATELLITE DEPICTS INCREASING CU
FIELD ALONG THE MISSISSIPPI RIVER AND INTO NORTHEAST
MISSOURI...WHERE STORM INITIATION IS EXPECTED OVER THE NEXT FEW
HOURS AND HAS BEEN INDICATED BY HIGH-RES GUIDANCE. ENVIRONMENT
PRIMED FOR SUPERCELL DEVELOPMENT...AND RECENT SPC MCD INDICATES
TORNADO WATCH LIKELY IN THE NEXT FEW HOURS WITHIN THE ENHANCED
RISK AREA TO OUR WEST/SOUTHWEST. BASED ON HIGH RES
GUIDANCE...EVOLUTION STILL APPEARS TO BE INITIATION 22-23Z TO OUR
WEST AND SOUTHWEST... WITH STORMS THEN SPREADING NORTHEAST INTO
THE FORECAST AREA AFTER 7-8 PM. LARGE HAIL...DAMAGING WIND AND
ISOLATED TORNADO THREAT WILL EXIST WITH SUPERCELLULAR STORMS
MOVING INTO THE CWA INITIALLY WITH OUR IL COUNTIES ALONG/SOUTH OF
I-80 LIKELY UNDER THE HIGHEST RISK. WIND AND TORNADO
THREAT...WHILE NOT ZERO...WILL LIKELY DIMINISH FURTHER NORTHEAST
INTO THE CHICAGO METRO WITH SOME DECREASE IN INTENSITY OF STORMS
POSSIBLE WITH GRADUAL DIURNAL DECREASE IN INSTABILITY. THE
POTENTIAL FOR SEVERE WEATHER WILL EXIST HOWEVER ALL THE WAY TO
LAKE MICHIGAN AND OUR EASTERN CWA COUNTIES AND STORMS ARRIVE IN
THE 9-10 PM TIME FRAME AND LAST THROUGH ABOUT MIDNIGHT OR 1 AM AS
THE SURFACE LOW LIFTS NORTHEAST INTO WISCONSIN AND ITS STRONG
TRAILING COLD FRONT PUSHES THROUGH THE AREA. SCATTERED SHOWERS OR
EVEN ISOLATED THUNDERSTORMS WILL LIKELY LINGER OVER PARTS OF NORTH
CENTRAL ILLINOIS AND THE IL/WI BORDER REGION AS THE UPPER TROUGH
LIFTS ACROSS THE AREA OVERNIGHT. SOME POTENTIAL FOR A FEW HIGH-
BASED INSTABILITY SHOWERS WEDNESDAY AFTERNOON NEAR THE WISCONSIN
BORDER WITH DEEP ADIABATIC LAPSE RATES.

WINDS WILL VEER FROM THE SOUTHEAST TO THE WEST-SOUTHWEST BEHIND
THE FRONT OVERNIGHT...INCREASING IN SPEED AND BECOMING GUSTY TO
40-45 MPH BY MORNING. MODEL FORECAST SOUNDINGS CONTINUE TO DEPICT
VERY DEEP MIXING TO AROUND 500-600 MB WEDNESDAY...WHICH LOOKS TO
SUPPORT WIND GUSTS TO/ABOVE 50 MPH BY MIDDAY ESPECIALLY ACROSS FAR
NORTHERN IL... WITH THE GRADIENT A BIT WEAKER TO THE SOUTH. DO
HAVE SOME CONCERNS THAT THE STRONGER GFS WINDS MAY BE A BIT
OVERDONE WITH BEST PRESSURE RISES TO OUR NORTH ACROSS WI...THOUGH
ENOUGH POTENTIAL EXISTS TO MAINTAIN OUR HIGH WIND WATCH ACROSS
COUNTIES GENERALLY NORTH OF I-80. HAVE ELECTED TO ISSUE A WIND
ADVISORY ACROSS THE SOUTHERN COUNTIES WHERE THERE IS MORE
CONFIDENCE THAT WINDS WILL REMAIN BELOW WARNING CRITERIA
(SUSTAINED 40 MPH /GUSTS 58 MPH). WITH GUSTY WINDS MODELS ARE
LIKELY TOO QUICK TO DECOUPLE WEDNESDAY EVENING...AND WILL LIKELY
SEE WINDY CONDITIONS CONTINUE INTO THE NIGHT.

WITH GOOD MIXING...HIGH TEMPS EXPECTED TO RANGE FROM MID 50S
NORTH TO LOW 60S SOUTH. LOWS EXPECTED IN THE MID-UPPER 40S
TONIGHT...MID TO UPPER 30S WEDNESDAY NIGHT.

RATZER

.LONG TERM...
244 PM CDT

THURSDAY THROUGH TUESDAY...

THE EXTENDED FORECAST WILL BE CHARACTERIZED BY AN AMPLIFYING
UPPER FLOW PATTERN ACROSS MUCH OF THE COUNTRY WHICH WILL LEAD
TO A STEADY COOLING TREND INTO THE WEEKEND BEFORE REVERSING EARLY
NEXT WEEK. COLDEST DAY TIME TEMPS WILL BE SLIGHTLY BELOW NORMAL
SATURDAY WITH ABOVE NORMAL TEMPS EITHER SIDE OF THAT. THE UPPER
LOW OVER THE WESTERN GREAT LAKES WILL BREAK DOWN THURSDAY ALLOWING
THE SURFACE LOW WHICH WILL BE OVER NORTHERN WISCONSIN AND THE U.P.
OF MICHIGAN TO QUICKLY WEAKEN. THIS WILL LEAVE A BROAD UPPER
TROUGH ACROSS THE EASTERN TWO-THIRDS OF THE U.S. WEAK ENERGY WILL
MOVE DOWN THE WESTERN FLANK OF THE TROUGH WHILE A DEEPER UPPER LOW
PIVOTS SOUTHWARD ACROSS QUEBEC WHICH THEN RE-DEVELOPS ACROSS NEW
ENGLAND FRIDAY. THE DEVELOPING SURFACE LOW OVER NEW ENGLAND WILL
AID IN THE SHARPENING OF THE BAROCLINIC ZONE REMNANT FROM THE OLD
GREAT LAKES LOW THEN DRAW IT SOUTHWARD AS A COLD FRONT. THERE MAY
BE ENOUGH FORCING/MOISTURE TO GENERATE SOME SHOWERS AS THE FRONT
PASSES LATER THURSDAY OR THURSDAY EVENING. COLDER AIR WILL SPREAD
INTO THE REGION FOR FRIDAY. SHOULD SEE HIGHS IN THE MID TO UPPER
40S FRIDAY. THE UPPER TROUGH SHARPENS OVER THE REGION SATURDAY
WHICH WILL LEAD TO A CHANCE FOR PRECIPITATION STARTING EARLY
SATURDAY. A RAIN SNOW MIX COULD OCCUR EARLY BEFORE WARMING INTO
THE LOWER/MID 40S CHANGES ANYTHING TO RAIN INTO SATURDAY
AFTERNOON. THE SIGNAL IS NOT ALL THAT GREAT FOR PRECIP BUT ENOUGH
TO WARRANT LOW CHANCE POPS. THE UPPER TROUGH MEANDERS EAST INTO
EARLY SUNDAY AS SHARP RIDGING BUILDS ACROSS WESTERN NORTH AMERICA.
ANY LINGERING PRECIP WOULD LIKELY CHANGE TO LIGHT SNOW SATURDAY
NIGHT BEFORE ENDING.

THE AREA WILL BE UNDER NORTHEASTERLY UPPER FLOW AS THE TROUGH
DEPARTS TO THE EAST AND RIDGING CONTINUES WEST. THIS WILL BE
FAVORABLE FOR SOME WEAK WAVES TRAVERSING THE FLOW PERHAPS LEADING
TO MINIMAL POPS CHANCES MONDAY. THE RIDGING WILL SHARPEN THE
BAROCLINIC ZONE OVER THE AREA INTO TUESDAY WHICH MAY BRING ANOTHER
CHANCE AT PRECIP. MEDIUM RANGE GUIDANCE IS IN FAIR AGREEMENT ON A
DEEP UPPER TROUGH PUSHING INTO THE WESTERN U.S. MID NEXT WEEK AND
A SURFACE LOW LIFTING NORTHEAST BUT DETAILS DIFFER QUITE A BIT. A
TREND TOWARD MILDER CONDITIONS FOR AT LEAST A SHORT TIME DOES LOOK
FAVORED FOR MID WEEK.

MDB

.FIRE WEATHER...441 PM CDT

STRONG WEST-SOUTHWEST WINDS WILL BE IN PLACE OVER THE AREA ON
WEDNESDAY WITH SUSTAINED WINDS IN EXCESS OF 20 MPH AND GUSTS OF
50 TO 55 MPH. WITH SUN EXPECTED FOR AT LEAST SEVERAL HOURS...AND
POSSIBLY ALL DAY IN PLACES...MIXING MAY ALLOW FOR HUMIDITY TO DIP
TO AROUND 25 PERCENT. RAINFALL TONIGHT IN ADDITION TO EXISTING FUEL
MOISTURE VALUES IN EXCESS OF 15 PERCENT SHOULD PREVENT TRUE RED
FLAG CRITERIA...BUT BREEZY AND DRY WEATHER CONDITIONS WILL AT
LEAST BE NEAR THRESHOLDS...AND WITH THE DEEPER MIXING 10 HOUR FUEL
MOISTURE VALUES COULD NEAR 10 PERCENT IF AREAS...PARTICULARLY
SOUTH OF THE CHICAGO AREA...ESCAPE THUNDERSTORMS TONIGHT.

MTF/KMD

.AVIATION...
FOR THE 00Z TAFS...

632 PM...LINE OF THUNDERSTORMS EXTENDING FROM EASTERN IA SOUTH TO
WESTERN IL WILL CONTINUE TO MOVE NORTHEAST ACROSS THE TERMINALS
THIS EVENING. MOST SHORT TERM GUIDANCE HAS AN ARRIVAL INTO THE
CHICAGO AREA AROUND 04Z BUT MAINTAINED 03Z TEMPO START TIMING FOR
NOW TO ACCOUNT FOR UNCERTAINTY AND THE POTENTIAL FOR STORMS TO
SPEED UP SOME. DURATION AT ANY ONE LOCATION LIKELY TO ONLY BE 1-2
HOURS AND AN END TIME BY 06Z SEEMS ON TRACK. TIMING INTO RFD A FEW
HOURS EARLIER.

GUIDANCE IS NOW SHOWING A PERIOD OF LIGHT RAIN OR SHOWERS
OVERNIGHT TOWARD SUNRISE AND THIS HAS BEEN A CHANGE FROM PREVIOUS
FORECASTS SO FOR NOW HAVE JUST INCLUDED TEMPO MENTION BUT A SHORT
PERIOD OF PREVAILING SHOWERS MAY BE NEEDED IF THESE TRENDS
CONTINUE.

EASTERLY WINDS 10-15KTS WITH HIGHER GUSTS WILL SLOWLY TURN MORE TO
THE SOUTHEAST THIS EVENING AND THEN SHIFT TO THE SOUTHWEST AFTER
MIDNIGHT. ONCE THE WINDS SHIFT...SPEEDS/GUSTS WILL QUICKLY
INCREASE AND WILL INCREASE FURTHER AFTER SUNRISE WEDNESDAY.
FORECAST SOUNDINGS SUGGEST PREVAILING GUSTS INTO THE MID/UPPER 40
KT RANGE FOR MOST OF THE DAY WEDNESDAY...FINALLY DIMINISHING EARLY
WEDNESDAY EVENING.

MAINTAINED IFR CIGS LATER THIS EVENING AS MOST GUIDANCE SUGGESTS
LOWER CIGS WILL REDEVELOP BUT CONFIDENCE REGARDING CIGS THIS
EVENING IS LOW AND MAY REMAIN MVFR OR BETTER UNDER STORMS/PRECIP
ARRIVE. TRENDS WILL NEED TO BE MONITORED FOR CIGS. CMS

.MARINE...
217 PM CDT

A STORM SYSTEM...CURRENTLY CENTERED OVER MISSOURI...WILL
STRENGTHEN RAPIDLY TONIGHT AS IT SHIFTS NORTH-NORTHEAST
INTO WISCONSIN BY DAYBREAK WEDNESDAY. THIS STORM SYSTEM WILL
PRODUCE A PERIOD OF STRONG EASTERLY WINDS (35 KT GALES)
LATE TONIGHT...FOLLOWED BY A PERIOD OF STRONG GALE FORCE WEST-
SOUTHWESTERLY WINDS ON WEDNESDAY. STORM FORCE GUSTS WILL ALSO
BE POSSIBLE ALONG THE WESTERN SHORES OF THE LAKE ON WEDNESDAY.
THESE WESTERLY WINDS WILL CONTINUE WEDNESDAY NIGHT INTO
THURSDAY...THOUGH WIND SPEEDS SHOULD GRADUALLY BE ON THE DOWNWARD
TREND. LATER IN THE WEEK EXPECT A COLD FRONT TO DROP SOUTH DOWN
THE LAKE...WITH A PERIOD OF GUSTY NORTHERLY WINDS EXPECTED.

KJB

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039...7 AM
WEDNESDAY TO 8 PM WEDNESDAY.

HIGH WIND WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022...7 AM WEDNESDAY
TO 8 PM WEDNESDAY.

IN...HIGH WIND WATCH...INZ001-INZ002...7 AM WEDNESDAY TO 8 PM
WEDNESDAY.

WIND ADVISORY...INZ010-INZ011-INZ019...7 AM WEDNESDAY TO 8 PM
WEDNESDAY.

LM...GALE WARNING...LMZ740-LMZ741...1 AM WEDNESDAY TO 10 AM WEDNESDAY.

SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS UNTIL 1 AM WEDNESDAY.

STORM WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...10 AM
WEDNESDAY TO 7 PM WEDNESDAY.

GALE WARNING...LMZ742-LMZ743-LMZ744-LMZ745...4 AM WEDNESDAY TO
10 AM WEDNESDAY.

SMALL CRAFT ADVISORY...NEARSHORE NORTHERLY IS TO MICHIGAN CITY IN UNTIL 4 AM
WEDNESDAY.

DENSE FOG ADVISORY...LMZ777-LMZ779 UNTIL 10 PM TUESDAY.

GALE WARNING...LMZ777-LMZ779...1 AM WEDNESDAY TO 1 AM THURSDAY.

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO

AREA FORECAST DISCUSSION

National Weather Service Lincoln IL

643 PM CDT TUE MAR 15 2016

.SHORT TERM...(Tonight)
ISSUED AT 312 PM CDT TUE MAR 15 2016

.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 312 PM CDT TUE MAR 15 2016

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 642 PM CDT TUE MAR 15 2016

.ILX Watches/Warnings/Advisories...
Wind Advisory from 7 AM to 8 PM CDT Wednesday for ILZ027>031-
036>038-040>057-061>063.

SHORT TERM...Barnes
LONG TERM...Smith
AVIATION...Barnes

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

632 PM CDT TUE MAR 15 2016

.SHORT TERM...
320 PM CDT

TONIGHT THROUGH WEDNESDAY NIGHT...

PRIMARY FORECAST FOCUS IS WITH SEVERE WEATHER POTENTIAL THROUGH
THIS EVENING...AND VERY WINDY CONDITIONS DEVELOPING LATER TONIGHT
AND CONTINUING THROUGH WEDNESDAY NIGHT.

WITH GOOD MIXING...HIGH TEMPS EXPECTED TO RANGE FROM MID 50S
NORTH TO LOW 60S SOUTH. LOWS EXPECTED IN THE MID-UPPER 40S
TONIGHT...MID TO UPPER 30S WEDNESDAY NIGHT.

RATZER

.LONG TERM...
244 PM CDT

THURSDAY THROUGH TUESDAY...

MDB

.FIRE WEATHER...

441 PM CDT

MTF/KMD

.AVIATION...
FOR THE 00Z TAFS...

.MARINE...
217 PM CDT

KJB

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039...7 AM
WEDNESDAY TO 8 PM WEDNESDAY.

HIGH WIND WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022...7 AM WEDNESDAY
TO 8 PM WEDNESDAY.

IN...HIGH WIND WATCH...INZ001-INZ002...7 AM WEDNESDAY TO 8 PM
WEDNESDAY.

WIND ADVISORY...INZ010-INZ011-INZ019...7 AM WEDNESDAY TO 8 PM
WEDNESDAY.

LM...GALE WARNING...LMZ740-LMZ741...1 AM WEDNESDAY TO 10 AM WEDNESDAY.

SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS
UNTIL 1 AM WEDNESDAY.

STORM WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...10 AM
WEDNESDAY TO 7 PM WEDNESDAY.

GALE WARNING...LMZ742-LMZ743-LMZ744-LMZ745...4 AM WEDNESDAY TO
10 AM WEDNESDAY.

SMALL CRAFT ADVISORY...NEARSHORE NORTHERLY IS TO MICHIGAN CITY IN
UNTIL 4 AM WEDNESDAY.

DENSE FOG ADVISORY...LMZ777-LMZ779 UNTIL 10 PM TUESDAY.

GALE WARNING...LMZ777-LMZ779...1 AM WEDNESDAY TO 1 AM THURSDAY.

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO

AREA FORECAST DISCUSSION

National Weather Service Lincoln IL

254 PM CDT MON MAR 14 2016

.SHORT TERM...(Tonight)
ISSUED AT 235 PM CDT MON MAR 14 2016

19z/2pm visible satellite imagery continues to show cloudy skies
across central Illinois: however, holes are developing in the
overcast...particularly upstream across Iowa/Missouri. Low-level
flow remains weak, but this drier air will eventually filter into
the area this evening, resulting in a partial clearing trend. With
some clearing taking place and winds staying quite light, think fog
will re-develop tonight. Mitigating factors for widespread dense
fog will be partial cloud cover and increasing southeasterly winds
after midnight. HRRR is showing fog forming across much of the area
this evening, then becoming locally dense after midnight. Think
this is a bit overdone, so will only carry patchy fog at this time.
Most high-res models are suggesting scattered convection will
develop overnight across northern Missouri into Iowa as a
strengthening low-level jet noses into that area. Some of this
activity could spill into west-central Illinois toward dawn, so have
included low chance PoPs for showers/thunder along and west of the
Illinois River well after midnight. Overnight lows will be in the
lower to middle 50s.

.LONG TERM...(Tuesday through Monday)
ISSUED AT 235 PM CDT MON MAR 14 2016

Forecast concern continues to revolve around the the threat for
severe weather over parts of central through east central Illinois
tomorrow afternoon and evening as a rather potent upper wave
pushes into the Midwest.

Looks as though scattered precip chances tomorrow will be tied to
the surface and 850 mb warm front in the morning, mostly across
the west and north, and then along the cold front during the mid
to late afternoon and early evening hours as the cap weakens due
to increasing low level convergence forecast along the accelerating
cold front. The GFS continues to be the fast model, although
recent runs have trended a bit slower tomorrow afternoon, while
the ECMWF is deepest and slowest with the surface and upper level
features. Due to the slower movement in the cold frontal passage
and the cap holding on a bit longer than previously forecast, it
appears the main time frame for the threat for scattered storms
across the forecast area will be roughly 4pm until 10 pm. The NAM
and ECMWF indicates the better low level shear profiles for any
persistent rotating storms capable of large hail and isolated
tornadoes will be along and north of I-74, while low level wind
profiles become more unidirectional further south by late in the
afternoon. However, the further south you go, the stronger the
capping inversion is, but believe at least widely scattered storms
will be possible as you head into southeast IL late tomorrow
afternoon through the evening hours. All models indicate steep low
and mid level lapse rates with 700-500 mb lapse rates approaching
8 C/KM tomorrow afternoon and evening suggesting the threat for
large hail along with damaging wind gusts, especially if the mode
transitions to a line of storms with time late in the afternoon
into the evening hours.

Models sweep the storms well off to our east by 03z with lingering
low chance POPs over the far north during the overnight hours
along with gusty winds as the deepening surface low shifts slowly
off to our north. Windy but mild conditions are expected Wednesday
before we see a gradual transition to cooler weather by the end of
the week and next weekend where afternoon temperatures will lower
into the upper 40s to lower 50s. As far as precip is concerned in
the extended, several weak waves are forecast to rotate south
around the deep upper low to our north which may produce some
isolated light showers with the main threat of rain coming along
over the weekend as the upper low to our north repositions itself
a bit further south over the Midwest. This will bring about
mentionable rain chances in the forecast on Saturday into Saturday
night.

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1252 PM CDT MON MAR 14 2016

IFR ceilings prevailed across central Illinois this morning:
however, ceilings are gradually rising into the MVFR category
early this afternoon as drier air tries to work into the area
from the southwest. Latest visible satellite imagery shows plenty
of breaks developing in the overcast upstream across southern Iowa
into Missouri, but with only very light low-level flow, think any
appreciable clearing will be delayed until this evening. Models
are in disagreement, with the NAM partially clearing things out
and the Rapid Refresh generally keeping it cloudy. Based on
satellite imagery, have sided with the more optimistic NAM. As
such, have removed ceilings at KSPI by 01z, then further northeast
to KCMI by 05z. If skies do indeed partially clear, light winds
and ample boundary layer moisture will lead to fog development
once again tonight. Have indicated that by including 2-4 mile
visbys at all terminals from mid-evening through the overnight
hours. A few WAA showers/thunder may develop overnight across
Iowa/Missouri, so have included VCSH at KPIA in case a few showers
spread that far eastward late tonight.

.ILX Watches/Warnings/Advisories...
NONE.
&&

SHORT TERM...Barnes
LONG TERM...Smith
AVIATION...Barnes

AREA FORECAST DISCUSSION

National Weather Service Lincoln IL

1138 PM CDT SUN MAR 13 2016

.UPDATE...
ISSUED AT 857 PM CDT SUN MAR 13 2016

Weather system that produced today`s rainfall has shifted off into
the Great Lakes, taking the bulk of the showers with it. However,
another system, currently spinning across Arkansas, is expected to
track northeast into the Ohio River Valley later tonight. This
system will bring a renewed threat for showers, especially south
of I-70. Southeast Illinois may also see a few thunderstorms with
this rainfall. Light winds between these two weather systems and
the moist ground from today`s rains will set the table for areas
of fog to develop. While there is the potential for dense fog to
develop, expect this threat to be mitigated to at least some
degree by the thick cloud cover in place.

Going forecast was in good overall shape. Main updates required
were to precipitation trends, with mainly dry conditions expected
for the next several hours until the next system draws closer.

.SHORT TERM...(Tonight)
ISSUED AT 245 PM CDT SUN MAR 13 2016

19z/2pm surface analysis shows a 1005mb low near KPIA, with
widespread light showers ongoing across the western half of the KILX
CWA. Further east and south, the steady precip has diminished to
widely scattered showers along/south of a Danville to Taylorville
line. The primary area of rain will continue to dissipate/retreat
northward as the low tracks into northern Illinois this evening.
Based on radar timing tools, most of the rain will be just north of
the CWA by early evening. Will therefore only carry chance PoPs
through the evening, with highest chances focused across the far
north around Galesburg and Lacon in closer proximity to the departing
low. A second area of low pressure currently over Oklahoma will
track into western Kentucky by Monday morning. This feature will
spread showers and a few thunderstorms into the SE CWA overnight, so
have carried likely PoPs along/south of I-70 after midnight
accordingly. Due to a very weak pressure gradient, winds will be
light and variable tonight. With nearly calm winds and ample low-
level moisture left behind by the rainfall today, think fog will re-
develop across the area tonight. HRRR continues to show widespread
fog across all but the SE where rain will be falling. The fog could
potentially become dense: however, timing and areal extent remain in
question. Will carry areas of fog in the forecast, but later shifts
may need to issue a Dense Fog Advisory if trends become apparent
later this evening.

.LONG TERM...(Monday through Sunday)
ISSUED AT 245 PM CDT SUN MAR 13 2016

Forecast focus this period on the threat for severe weather over
parts of the forecast area Tuesday afternoon/evening.

Compact upper level storm tracking east-northeast through Arkansas
then into western Ky Monday morning will bring showers and isolated
storms to parts of southeast Illinois, at least through the morning
hours, while further north, the low clouds, fog and shower chances
end from northwest to southeast during the morning with only the
southeast quarter of the forecast area still seeing the threat for
afternoon showers. Forecast soundings continue to hold on to the low
level moisture across the area into the afternoon hours so the
prospects for much in the way of sunshine are low, with most areas
seeing afternoon temperatures rise into the low to mid 60s.

As the deepening upper wave for Tuesday pushes across the Rockies
and into the high Plains late Monday night, the threat for at
least scattered showers and storms will increase out to our west
Monday night with chances increasing over our western counties
after Midnight. Still some significant differences with respect to
how quickly the upper wave tracks east across the Great Lakes with
the ECMWF the slowest, while the GFS remains the fastest in pushing
the front to our east by late afternoon Tuesday. The ECMWF digs
the shortwave southeast in response to ridging over the eastern
Pacific and that is tending to slow the system down compared to
the more progressive look from the GFS and SREF ensemble solutions.
You would have thought we would have seen a slowing trend from the
GFS, NAM and SREF solutions by now, but up through the 12z models
runs of today, we haven`t, which keeps confidence on timing and
storm mode in our area on Tuesday low.

All models continue to show deep layer shear associated with the
upper wave as it becomes negatively tilted late in the day Tuesday
with strong low level turning of the winds seen on the hodographs,
especially off the NAM. 850 mb winds depicted on the ECMWF were
southeasterly at 40-45 kts in the 21z-00z time frame across our
north. SREF forecasts of surface dew points were a bit more
conservative on Tuesday afternoon, compared with the NAM, with
mostly middle 50s forecast across our area, while the NAM near
60 degree dew points which pushed SB cape values above 2500 J/KG
over the eastern half of the forecast area Tuesday afternoon.
Forecast soundings off the NAM and GFS continue to show a capping
inversion in place at least into the early afternoon hours before
low level convergence starts to increase in the 925-850 mb layer
just ahead of the front, which should allow convection to
develop. The 4km NAM-WRF reflectivity simulations suggest the
development of storms off to our east after 21z just ahead of the
increasing low level moisture convergence. However, if the timing
off the ECMWF is correct, storms will develop by mid afternoon
further west, along or just west of Interstate 55 and streak east-
northeast through the rest of the forecast area by 02z.

Based off the low level wind profiles seen on the ECMWF, discrete
supercells capable of large hail (with 700-500 mb lapse rates over
7.0 C/KM) damaging winds and isolated tornadoes will be possible
for a few hours, especially if the high dew points seen on the NAM
verify, before cells consolidate into a fast moving line with
mainly a damaging wind threat through late afternoon into early
evening. If the GFS verifies, storms will develop in areas east of
I-55 and be out of our area by 00z. Still quite a bit of uncertainty
with the timing of the shortwave and attendant cold front for late
Tuesday afternoon and evening. For now, will continue to mention
the higher probabilities for damaging straight line winds and hail
in the HWO for Tuesday, but as mentioned above, if the low level
moisture increases more than what is advertised in most models,
the tornado threat will start to become a concern as well Tuesday
afternoon.

Highest POPS for Tuesday will continue to be across the north with
progressively lower POPs as you head south during the afternoon and
evening. Strong gusty southerly winds are expected by late morning
into the afternoon hours as the deepening upper and surface lows
track to our west-northwest. Shower chances start to decrease
later Tuesday night as the front shifts well off to our east and
then windy conditions expected Wednesday in the wake of the storm
as it tracks slowly east across north-central Wisconsin.
Temperatures at least initially, will not cool off much on Wed.
with upper 50s to lower 60s expected during the afternoon, with
the gradual cooling trend starting on Thursday and continuing
through Sunday with temperatures returning closer to normal for
this time of year. Our next chance for rain across central IL will
be next weekend, but POPs were kept low this far out as model
spread was large.

.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1134 PM CDT SUN MAR 13 2016

IFR conditions will continue to be a concern across the central
Illinois terminals well into Monday. Showers across the region,
associated with a couple separate weather systems, will remain
considerably less numerous than they were earlier today, but
fog/stratus will be widespread. Conditions should gradually
improve to MVFR Monday afternoon, with VFR likely by Monday
evening as the systems pull further away. Light/variable winds
should prevail through the period.

.ILX Watches/Warnings/Advisories...
NONE.
&&

UPDATE...BAK
SHORT TERM...Barnes
LONG TERM...Smith
AVIATION...BAK

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

1122 PM EDT TUE MAR 15 2016

.SYNOPSIS...
ISSUED AT 1121 PM EDT TUE MAR 15 2016

A COLD FRONT WILL SWEEP EAST OVERNIGHT ACCOMPANIED BY SHOWERS AND
THUNDERSTORMS. SOME OF THESE STORMS COULD BE SEVERE WITH LARGE
HAIL AND LOCALLY DAMAGING WINDS POSSIBLE...ESPECIALLY WEST OF A
CASSOPOLIS TO PLYMOUTH TO LOGANSPORT LINE. WEDNESDAY MORNING LOWS
WILL RANGE FROM THE UPPER 40S TO THE LOWER 50S. VERY WINDY
CONDITIONS ARE EXPECTED ON WEDNESDAY WITH WIND GUSTS TO 50
MPH...WITH HIGH TEMPERATURES REACHING THE UPPER 50S TO LOWER 60S.

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 334 PM EDT TUE MAR 15 2016

FOCUS OF THE NEAR TERM IS SEVERE POTENTIAL LATER THIS EVENING.
CONTINUING TO MONITOR IMPENDING STORM DEVELOPMENT ACROSS NE MO
DURING THE NEXT FEW HOURS. EXPECTED TIMING OF STORM INITIATION AND
FRONTAL FORCING INTO THE AREA LENDS A RATHER CONDITIONAL RISK FOR
SEVERE WEATHER ACROSS THE LOCAL FORECAST AREA. LATEST CONSENSUS
TRENDS FROM HIGH RES GUIDANCE INDICATES POTENTIAL STORM ARRIVAL
INTO THE WESTERN PART OF THE FORECAST AREA AROUND 04Z...WITH
VARYING DEGREES OF SOLUTIONS EXPANDING STORM COVERAGE EASTWARD
THROUGH THE FORECAST AREA THROUGH THE 09-11Z TIMEFRAME. THIS
FORECAST THINKING IS REFLECTED IN THE GRIDS WITH CAT/HIGH LIKELY
POPS SHIFTING EAST THROUGH THE FORECAST AREA DURING THIS
TIMEFRAME.

A FEW QUESTIONS REMAIN WITH RESPECT TO THE SEVERE RISK FOR OUR
FORECAST AREA AND OVERALL COVERAGE OF STORMS. SFC CYCLONE IN
CENTRAL MO WILL DEEPEN AND TRACK NORTHWARD THIS AFTERNOON/EVE
AHEAD OF NEGATIVELY TILTED 500MB TROF...WITH NOSE 100-130KT 250MB
JET AND 80- 100KT 500MB JET PUSHING INTO THE REGION BETWEEN 03Z
AND 06Z. THE DYNAMICS ARE CERTAINLY THERE FOR A SIGNIFICANT SEVERE
WEATHER EVENT JUST UPSTREAM IN INTO THE WESTERN PORTION OF THE
FORECAST AREA...WITH STRONG UPPER LEVEL DIV...STRONG SFC FRONTAL
FORCING...INCREASING LOW LVL JET AND SFC-06KM BULK SHEAR VALUES
INCREASING TO 50-65KTS AHEAD OF THE FRONT. THERMODYNAMICALLY...
SBCAPE VALUES BETWEEN 1500-2500 J/KG NOTED CENTRAL IL JUST AHEAD
OF THE SFC COLD FRONT BETWEEN 00Z-03Z. STOUT EML NOTED WITH MID
LVL LAPSE RATES ON THE ORDER OF 8C/KM ADVECTING THROUGH THE REGION
AHEAD OF THE FRONT. THIS ENVIRONMENT IS VERY FAVORABLE FOR LONG
LIVED AND FAST MOVING SUPERCELLS WITH DAMAGING WINDS...LARGE HAIL
AND TORNADOES. HOWEVER...CONFIDENCE IS OVERALL LOW FOR TORNADO
POTENTIAL...LOW TO MEDIUM FOR WIND AND MEDIUM TO HIGH TO
HAIL...WITH EXPLANATION BELOW.

HOWEVER...THE MAIN QUESTION FOR OUR FORECAST AREA IS THE TIMING
OF THE STORMS AND POTENTIAL BOUNDARY LAYER STABILIZATION AFTER
03Z. THE STORMS WILL BE INITIALLY SFC BASED ACROSS CENTRAL IL THIS
EVENING. WITH THE LOW 60F DEWPOINTS AND LCLS BETWEEN 500-700M IN
CENTRAL IL...A DAMAGING WIND...HAIL AND TORNADO RISK ARE ALL IN
PLAY. AS THE STORMS MOVE INTO OUR FORECAST AREA TOWARDS 03Z...LOW
LEVEL JET RAMPS UP WITH INCREASINGLY BACKED SFC FLOW ACROSS THE
SOUTHWEST PART OF THE FORECAST AREA. BY 03Z...LARGE CURVED
HODOGRAPHS NOTED W/ HI RES FORECAST SOUNDINGS...WITH 0-1KM SRH
VALUES IN THE 300-500 RANGE...INCREASING THROUGH 06Z. WHILE LOW
LEVEL DYNAMICS ARE VERY CONCERNING FOR TORNADO POTENTIAL ALONG AND
SOUTHWEST OF A LAPORTE TO PERU LINE...STORMS MAY BE TRANSITIONING
TO A MORE ELEVATED NATURE AS NEAR SURFACE BL COOLS.
HOWEVER...RIGHT ALONG AND AHEAD OF THE FRONT IN THE 03-06Z TIME
FRAME...THERE MAY BE A CROSSHAIR OF LOW ENOUGH LCLS AND ENOUGH SFC
BASED INSTABILITY TO STRETCH THE HIGHLY SHEARED LOW LEVEL
ENVIRONMENT FOR A LOW TO MEDIUM TORNADO RISK. MUCH OF THIS IS
CONDITIONAL ON UPSTREAM SUPERCELL DEVELOPMENT AND STORM EVOLUTION.
HOWEVER IF THINGS COME TO FRUITION UPSTREAM...A TORNADO RISK COULD
PERSIST INTO THE WESTERN PART OF THE FORECAST AREA BETWEEN 03Z AND
06Z ALONG WITH A LARGE HAIL AND DAMAGING WIND THREAT. RIGHT
NOW...CURRENT THINKING IS TORNADO THREAT IS OVERALL LOW...AS
EXPECTED BL STABILIZATION AROUND THE 03Z TIME FRAME WILL QUICKLY
PRECLUDE TORNADO POTENTIAL.

OTHERWISE...EXPECTING STORMS TO BECOME MAINLY ELEVATED TOWARDS
06Z AND BEYOND. WITH ELEVATED LONG/SKINNY CAPE PROFILES FROM
500-1500 J/KG AND MID LVL LAPSE RATES BETWEEN 7-7.5C/KM...THE MAIN
THREAT WILL QUICKLY TRANSITION TO LARGE HAIL WITH ANY STORMS
ACROSS THE AREA...WITH DAMAGING WINDS POSSIBLE WITH STRONG WIND
FIELD ALOFT. OVERALL FROM 06Z AND BEYOND...STORM COVERAGE SHOULD
BECOME MORE SCATTERED WITH A GENERALLY WEAKENING TREND. ANY
REMAINING STORMS/PRECIP SHOULD EXIT THE AREA TO THE E/NE JUST
BEFORE 12Z.

FOCUS THEN SHIFTS TO GUSTY WINDS WEDNESDAY WITH STRONG PRESSURE
GRADIENT/LOW LEVEL JET ROUNDING THE SW QUADRANT OF THE SFC LOW.
850MB FLOW PEAKS ACROSS THE NW PART OF THE FORECAST AREA WEDNESDAY
MORNING AROUND 60 KTS...WITH 925MB FLOW IN THE 40-50 KT RANGE.
CURRENT THINKING IS WIDESPREAD WINDS 30 MPH GUSTING UP TO 50 MPH
THROUGH THE DAY...PARTICULARLY WITH MOSTLY SUNNY SKIES ALLOWING
FOR AMPLE MIXING. HAVE ISSUED A WIND ADVISORY FROM 12Z THROUGH 00Z
WEDNESDAY. ASIDE FROM A SLIGHT CHANCE FOR RAIN SHOWERS MAINLY IN
SRN LOWER MICHIGAN DURING THE MORNING...CONDITIONS ARE EXPECTED TO
BE DRY FOR MOST OF THE DAY.

.LONG TERM...(THURSDAY MORNING THROUGH TUESDAY)
ISSUED AT 334 PM EDT TUE MAR 15 2016

LONG TERM BEGINS THURSDAY MORNING WITH VERTICALLY STACKED LOW
PRESSURE CENTERED OVER NORTHERN LAKE MICHIGAN. THIS LOW WILL FILL
AND SINK SOUTHWARD ACROSS THE AREA THURSDAY AND THURSDAY NIGHT IN
RESPONSE TO SOUTHWARD BUILDING CENTRAL CANADIAN RIDGE. THIS MAY
BRING SCATTERED PRECIP TO THE AREA THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT AS THE PINCHED OFF TROUGH SINKS SOUTH OF THE AREA.
THIS WILL ALSO USHER IN A COOLER PERIOD WITH TEMPS AT OR BELOW
NORMAL INTO EARLY NEXT WEEK.

PRECIP CHANCES WILL INCREASE AGAIN SATURDAY AND SUNDAY AS A CUT OFF
LOW ON WESTERN PERIPHERY OF ELONGATED TROUGH SPREADS EASTWARD
BETWEEN THE SOUTHERN GREAT LAKES AND OHIO VALLEY AS THE CANADIAN
RIDGE SHIFTS FROM THE GREAT LAKES TO THE NORTHEAST US. MODELS STILL
VARY WITH HOW TO HANDLE THIS CUTOFF LOW...SO LEFT POPS IN THE LOW
CHANCE RANGE SAT THROUGH SUN. PTYPE MAY BE AN ISSUE WITH ANY PRECIP
SAT NIGHT AND EARLY SUN...WITH MUCH OF THE SOUNDING BELOW FREEZING.

GENERAL WARMING TREND WILL BEGIN EARLY NEXT WEEK. MODELS DIVERGE
GREATLY WITH FORECAST DETAILS BEYOND MONDAY...BUT STILL EXPECT A
RETURN TO NORMAL TO JUST ABOVE NORMAL TEMPS TOWARDS THE MIDDLE OF
NEXT WEEK.

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 802 PM EDT TUE MAR 15 2016

CHANGES WRT 00 UTC TAFS INCLUDE LATER TSRA TIMING ALONG WITH SIG
WIND SPEED/GUST INCREASES POST FRONTAL FOR WED. LATEST RAP AND
TIMING OF ONGOING UPSTREAM CONVECTION SUGGEST A LATER 1-2 HOURS OF
THE BEST WINDOW FOR CONVECTION. WITH PIVOT POINT OF NORTHERN
EXTENT OF LOWER 60S SURFACE DEWPOINTS LIKELY REMAINING SOUTH OF
KSBN AND WITH EFFECTIVE POST FRONTAL SCOUR RELEGATED IFR
CONDITIONS TO TEMPO GROUP VS STANDALONE CHANGE GROUP. WITH
NORTHERN INDIANA IN CENTRAL BULLSEYE OF N/S 11MB/3 HR SURFACE
PRESSURE FALL/RISE COUPLET AT 12 UTC FOLLOWED BY DEEPENING MIXING
BY MIDDAY WITH SWRLY SURFACE WINDS ON THE ORDER OF 25G40 KTS
ANTICIPATED.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WIND ADVISORY FROM 8 AM EDT /7 AM CDT/ TO 8 PM EDT /7 PM CDT/
WEDNESDAY FOR INZ003>009-012>018-020-022>027-032>034.

MI...WIND ADVISORY FROM 8 AM TO 8 PM EDT WEDNESDAY FOR MIZ077>081.

OH...WIND ADVISORY FROM 8 AM TO 8 PM EDT WEDNESDAY FOR OHZ001-002-004-
005-015-016-024-025.

LM...GALE WARNING FROM 5 AM TO 8 PM EDT WEDNESDAY FOR LMZ043-046.

SYNOPSIS...MURPHY
SHORT TERM...NG
LONG TERM...NG
AVIATION...MURPHY

VISIT US AT WW.WEATHER.GOV/IWX

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AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

803 PM EDT TUE MAR 15 2016

.SYNOPSIS...
ISSUED AT 750 PM EDT TUE MAR 15 2016

A WARM FRONT WILL MOVE ACROSS THE AREA THIS EVENING... BRINGING A
WARM UP IN TEMPERATURES ACROSS THE AREA WITH HIGHS BEING REACHED
DURING THE MID EVENING HOURS AS TEMPERATURES REACH WELL INTO THE
60S TO POSSIBLY LOWER 70S INTO WEST CENTRAL INDIANA. A COLD FRONT
WILL SWEEP EAST LATE TONIGHT ACCOMPANIED BY SHOWERS AND
THUNDERSTORMS. SOME OF THESE STORMS COULD BE SEVERE WITH LARGE
HAIL AND LOCALLY DAMAGING WINDS POSSIBLE LATE TONIGHT. WEDNESDAY
MORNING LOWS WILL RANGE FROM THE UPPER 40S TO THE LOWER 50S. VERY
WINDY CONDITIONS ARE EXPECTED ON WEDNESDAY WITH WIND GUSTS TO 50
MPH.