Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/23/15
AREA FORECAST DISCUSSION
NWS NEW YORK NY
635 PM EDT SAT MAR 21 2015
.SYNOPSIS...
A COLD FRONT CROSSES THE TRI-STATE INTO THE EARLY MORNING
HOURS...THEN CANADIAN HIGH PRESSURE THEN BUILDS IN THROUGH
TUESDAY. THE HIGH MOVES OFF SHORE WEDNESDAY AS LOW PRESSURE
APPROACHES FROM THE WEST. A COLD FRONT ASSOCIATED WITH THE LOW
CROSSES THE REGION THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE
BUILDS IN FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
RADAR INDICATING SOME LIGHT RAIN SHOWERS OR SPRINKLES POSSIBLE
COMING INTO THE LOWER HUDSON VALLEY WITH RETURNS OF 16 TO 20 DBS.
ALSO HRRR PICKING UP ON SOME SPRINKLES THROUGH 02Z. SO ADDED
SPRINKLES ACROSS ORANGE...PUTNAM...ROCKLAND...AND WESTCHESTER
COUNTIES.
ALSO...TEMPERATURES HAVE BEEN SLOW TO DROP AND ADJUSTED UPWARD
THROUGH THIS EVENING.
WITH 700-500 HPA TROUGH AXIS ALREADY TO THE N/E THE BEST FORCING
SHOULD STAY TO OUR N/E TONIGHT...ALLOWING FOR SURFACE COLD FRONTAL
PASSAGE THIS EVENING/THE EARLY MORNING HOURS TO BE DRY.
FOR LOWS TONIGHT...USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES. LOWS SHOULD BE AROUND 5 DEGREES BELOW
NORMAL. TEMPERATURES WILL NOT FALL OFF THAT MUCH THIS EVENING
AHEAD OF THE COLD FRONT...BUT SHOULD FALL OFF FAIRLY RAPIDLY AS
MODERATE TO STRONG LOW LEVEL COLD ADVECTION ON SETS BEHIND THE
FRONT DUE TO INCREASING NW WINDS.
NW WINDS SHOULD GUST TO AROUND 20-30 MPH BY AROUND SUNRISE...WITH
WIND CHILLS GENERALLY FROM THE MID TEENS TO AROUND 20.
GIVEN DELAY IN FALL OFF OF TEMPERATURES...AND SOME UNCERTAINTY IF
NYC AND PARTS OF LONG ISLAND WILL REACH FREEZING...WILL HOLD OFF
ON ISSUING AN SPS FOR BLACK ICE FOR NOW.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
NW FLOW ALOFT SUNDAY AND SUNDAY NIGHT AS A PROTUBERANCE OF THE
POLAR VORTEX PASSES TO OUR N THEN NE ACROSS SE CANADA/FAR N NEW
ENGLAND. GIVEN ASSOCIATED LOW LEVEL COLD POOL...WILL BE A FIGHT
BETWEEN DOWN SLOPING LOW LEVEL FLOW AND LOW LEVEL INSTABILITY FOR
EXTENT OF CLOUD COVER BY SUNDAY AFTERNOON. FOR NOW GOING MAINLY
MOSTLY SUNNY ON SUNDAY.
FOR HIGHS SUNDAY A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 875 TO 850 HPA PER BUFKIT
SOUNDINGS WAS USED. HIGHS SHOULD BE AROUND 15 DEGREES BELOW NORMAL
- WITH MOST AREAS STRUGGLING TO REACH THE LOWER TO MID 30S AND
HIGHER ELEVATIONS STRUGGLING TO REACH THE 30 DEGREE MARK.
NW WINDS GUSTING TO AROUND 30 MPH...WITH SOME OCCASIONAL GUSTS TO
35 OR MAYBE EVEN 40 MPH WILL KEEP WIND CHILLS MAINLY FROM THE
UPPER TEENS TO MID 20S.
FOR LOWS SUNDAY NIGHT A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES WAS USED...WITH VALUES FORECAST TO BE AROUND 15
DEGREES BELOW NORMAL. WINDS DIMINISH THROUGH THE NIGHT...BUT STILL
SHOULD PRODUCE WIND CHILLS MAINLY IN THE SINGLE DIGITS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
SURFACE CANADIAN HIGH PRESSURE WILL BE BUILDING INTO THE AREA MONDAY
INTO TUESDAY NIGHT WHILE ALOFT A WEAK UPPER TROUGH REMAINS ACROSS
THE NORTHEAST AND INTO EASTERN CANADA. A WEAK SHORTWAVE ROTATES
THROUGH TUESDAY...HOWEVER THERE IS LITTLE MID AND LOWER LEVEL
SUPPPORT...WITH SUBSIDENCE ASSOCIATED WITH THE HIGH...AND LITTLE
MOISTURE. THE SHORTWAVE MOVE THROUGH WITH JUST SOME HIGH CLOUDINESS.
WITH THE RIDGE MOVING OFFSHORE WEDNESDAY WARM ADVECTION SETS UP LATE
TUESDAY NIGHT INTO WEDNESDAY WITH A DEVELOPING WARM FRONTAL BOUNDARY
TO THE WEST AND SOUTH...THROUGH CENTRAL PENNSYLVANIA TO SOUTHERN NEW
JERSEY. LIGHT SHOWERS WILL BE POSSIBLE BY WEDNESDAY AFTERNOON WITH
INCREASING ISENTROPIC LIFT WITH THE FRONT. IN ADDITION THE WARM
ADVECTION WILL QUICKLY REPLACE ANY COLD AIR AND ALL LIQUID
PRECIPITATION IS EXPECTED.
MINOR DIFFERENCES WITH THE TIMING OF THE COLD FRONT LATE THURSDAY
INTO THURSDAY NIGHT. HAVE BROUGHT THE FRONT THROUGH SLOWLY...THURSDAY
NIGHT...MORE TOWARD THE ECMWF...AS THE FLOW BECOMES MORE
PARALLEL TO THE FRONT.
BROAD UPPER TROUGH REMAINS INTO NEXT WEEKEND AS SURFACE HIGH SLOWLY
BUILDS. COULD BE SOME POST FRONTAL RAIN SHOWERS...RAIN AND SNOW
SHOWERS INLAND...AND WILL KEEP SLIGHT CHANCE POPS FRIDAY INTO
SATURDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE REMAINS IN PLACE THIS AFTERNOON. A COLD FRONT PASSES
THROUGH TONIGHT.
VFR. COULD BE TEMPO MVFR THIS AFTN WITH CIGS 2000-3000 FEET. NOT
ENOUGH CONFIDENCE TO INCLUDE IN TAFS.
SW-WSW WINDS AROUND 10 KT THIS AFTERNOON. WINDS VEER TO THE
WEST/NORTHWEST JUST BEFORE MIDNIGHT. GUSTS OVERNIGHT MIGHT BE ONLY
OCCASIONAL FOR SOME LOCATIONS. SUSTAINED WINDS AND GUSTS INCREASE
DURING SUNDAY MORNING.
OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
.SUN PM...VFR. NW GUSTS 20-25 KT.
.MON...VFR. NW GUSTS AROUND 20 KT.
.TUE...VFR.
.WED...CHANCE OF SUB-VFR/SHRA IN AFTN.
.THU...CHC OF SUB-VFR/SHRA. SW GUSTS 20-25 KT.
&&
.MARINE...
SE SWELLS PERSIST ON THE COASTAL OCEAN WATERS...KEEPING THE SEAS
UP. WINDS INCREASE BEHIND A COLD FRONT TONIGHT...BRINGING GUSTS TO
SCA LEVELS ON ALL WATERS AFTER MIDNIGHT TONIGHT...WITH SCA GUSTS
CONTINUING ON ALL WATERS THROUGH SUNDAY AFTERNOON. SCA LEVEL GUSTS
ARE EXPECTED TO CONTINUE ON THE COASTAL OCEAN WATERS...EASTERN
SOUND AND THE BAYS OF LONG ISLAND SUNDAY NIGHT. AS A RESULT HAVE
EXTENDED THE SCA ON ALL WATERS THROUGH SUNDAY AFTERNOON AND ON THE
COASTAL OCEAN WATERS...EASTERN SOUND AND THE BAYS OF LONG ISLAND
THROUGH SUNDAY NIGHT.
HIGH PRESSURE WILL BE BUILDING INTO THE WATERS MONDAY AND
MOVE EAST OF THE WATERS WEDNESDAY. WIND AND SEAS WILL REMAIN BELOW
SMALL CRAFT LEVELS MONDAY THROUGH WEDNESDAY.
AS THE HIGH MOVES OFF SHORE WEDNESDAY AND A LOW APPROACHES FROM THE
WEST AN INCREASING SOUTHERLY FLOW WILL DEVELOP. ON THE OCEAN SMALL
CRAFT GUSTS WILL BE POSSIBLE BY THURSDAY...AND SEAS BUILD TO 5 FT OR
HIGHER BY THURSDAY. SMALL CRAFT CONDITIONS REMAIN INTO THURSDAY
NIGHT. A COLD FRONT CROSSES THE WATERS THURSDAY NIGHT AND HIGH
PRESSURE BUILD IN FROM THE WEST. WIND AND SEAS SUBSIDE TO BELOW
SMALL CRAFT THURSDAY NIGHT AND REMAIN BELOW FRIDAY.
&&
.HYDROLOGY...
DRY THROUGH TUESDAY NIGHT. AROUND A HALF INCH OF PRECIPITATION IS
EXPECTED FROM WEDNESDAY AFTERNOON THROUGH THURSDAY NIGHT.
ICE BREAKUP/MOVEMENT ACROSS THE LOWER HUDSON VALLEY AND
CONNECTICUT RIVERS/STREAMS IS EXPECTED TO BE LIMITED THROUGH
EARLY NEXT WEEK WITH LITTLE RUNOFF AND BELOW SEASONABLE TEMPS.
ISOLATED ICE JAMS ARE POSSIBLE...WHICH IF THEY OCCUR...COULD
RESULT IN LOCALIZED FLOODING. SINCE ICE JAM FLOODING IS
UNPREDICTABLE AND SUDDEN...INTERESTS ALONG ICE COVERED RIVERS
SHOULD MONITOR NWS FORECASTS FOR THE LATEST INFORMATION.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT SUNDAY
FOR ANZ335-338.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EDT MONDAY
FOR ANZ330-340-345.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT/MET
NEAR TERM...MALOIT/MET
SHORT TERM...MALOIT
LONG TERM...MET
AVIATION...JC
MARINE...MALOIT/MET
HYDROLOGY...MALOIT/MET
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
950 AM EDT SAT MAR 21 2015
.DISCUSSION... A REVIEW OF THE MORNING SOUNDING PARAMETERS INDICATE
ONLY A MARGINALLY FAVORABLE SETUP FOR DEVELOPMENT OF AFTN SHOWERS.
MID LEVEL CAPPING PRESENT EARLY FRIDAY HAS ERODED SOME...HOWEVER H5
TEMPS REMAIN A RELATIVELY WARM -7C. IN ADDITION...THERE HAS BEEN
SOME DRYING OF THE COLUMN TO AROUND 1.4 IN PWAT WITH DEEPER LAYER
WLY/NW STEERING. CONSIDERING ALL FACTORS WHILE GIVEN LIKELIHOOD OF
ECSB BOUNDARY AND MID TO LATE AFTERNOON COLLISIONS WL KEEP AN ISOLD
MENTION OF SHOWERS IN THE AFTERNOON FORECAST WHILE EXPANDING THE
MENTION TO INCLUDE THE TREASURE CST AND LAKE OKEE AREAS AS INDICATED
BY LTST 2KM HRRR WHERE CVG IS THE HIGHEST AT MID TO LATE AFTN.
FORECAST UPDATE HAS BEEN SENT TO REMOVE THE EARLIER DENSE FOG
ADVISORY AND REVISING THE PRECIP CVG AS WELL.
CURRENTLY...(FROM PREV DISC) A FRONTAL BOUNDARY TRAILED FROM LOW
PRESSURE ALONG THE CAROLINA COAST WITH THE SOUTHERN END BECOMING ILL
DEFINED OVER EAST CENTRAL FLORIDA. SURFACE WIND AND THETA E FIELDS
FROM THE GFS SUGGEST THAT THE TAIL OF THE FRONT ACTUALLY HOOKS BACK
NORTHWARD ALONG THE COAST FROM ABOUT BREVARD TO VOLUSIA.
THE CHANCE FOR CONVECTION LOOKS LOW AGAIN AND MAINLY CONFINED TO SEA
BREEZE INTERACTIONS WHERE THE REMNANT MOISTURE FROM THE
AFOREMENTIONED SURFACE BOUNDARY EXISTS. THE GFS SEEMS TO HAVE THE
BEST SOLUTION...THOUGH THE LOCAL WRF WHICH IS BASED OFF THE
NAM...GENERATES LITTLE PRECIP. WE WILL HAVE TO SEE BUT OVERALL THE
NAM LOOKS TOO DRY.
TEMPS WILL RISE QUICKLY INTO THE MID/UPPER 80S AGAIN EXCEPT FOR SOME
LOWER 80S RIGHT ALONG THE COAST.
&&
.AVIATION...AFT 14Z VFR IS EXPECTED EXCEPT MAYBE RIGHT ALONG THE
COAST FROM KDAB-KTIX WHERE SOME STRATUS MAY LINGER A LITTLE LONGER.
SMALL SHOWER CHANCES AREAWIDE THIS AFTERNOON WITH AFFECTED LOCATIONS
POSSIBLY SEEING A PERIOD OF MVFR CONDS. EXPECT PATCHY FOG LATE
TONIGHT...THOUGH EXTENSIVE MID/HIGH CLOUDS SHOULD BE MORE OF A
LIMITING FACTOR.
&&
.MARINE... TODAY-TONIGHT...WINDS LOOK VARIABLE 5 KNOTS THIS MORNING
THEN WITH THE SEA BREEZE CIRCULATION THEY WILL BECOME ONSHORE 5-10
KNOTS IN THE AFTERNOON. THE MODELS THEN SHOW SURFACE HIGH PRESSURE
SLIDING SEAWARD TONIGHT WITH WINDS TURNING SOUTHEAST TO SOUTH 8-12
KNOTS. SOME SHOWERS WILL MOVE OFF THE BARRIER ISLANDS AND OVER THE
ADJACENT ATLC FROM LATE AFTN INTO THE EARLY EVENING
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
JP/AC
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1016 PM CDT SUN MAR 22 2015
.SHORT TERM...
308 PM CDT
THROUGH TUESDAY NIGHT...
THE FOCUS ON THE FIRST THREE DAYS OF THE FORECAST WAS
SNOW IN THE FIRST 24 HOURS AND THEN RAIN TIMING...AMOUNTS...AND
WHETHER THUNDER WILL ACCOMPANY ON TUESDAY AFTERNOON AND NIGHT. SO
IN OTHER WORDS...A CLASSIC SPRINGTIME PATTERN IN THE MIDWEST.
THE AFTERNOON REGIONAL RADAR MOSAIC INDICATES A NARROW CORRIDOR
OF REFLECTIVITY PERSISTING FROM FAR SOUTHERN MN THROUGH THE NORTH
CHICAGO METRO. TO THE IMMEDIATE NORTH OF THE IL STATE LINE AND
FURTHER NORTHWEST THIS CORRIDOR HAS FILLED IN WITH POCKETS OF
HEAVY SNOW AND ONE QUARTER MILE VISIBILITY. DESPITE THIS NEAR
PROXIMITY...THINK THAT FAR NORTHERN ILLINOIS WILL MAINLY SEE SOME
SPORADIC LIGHT SNOW THROUGH THIS EVENING. THE NORTHERN PARTS OF
WINNEBAGO...BOONE...AND INTO MCHENRY AND LAKE COUNTIES COULD GET
INTO A BRIEF SNOW BURST OR TWO...BUT ANYTHING OF THAT NATURE
SHOULD BE BRIEF AS OBSERVATIONAL TRENDS OF VISIBILITY AND DEW
POINTS INDICATE DRY AIR WILL OFFSET SOME OF THESE RATES COMING OUT
OF THE CLOUD DECK.
OF MORE CONCERN IS LATER TONIGHT AS THE LOW AMPLITUDE BUT WELL-
DEFINED SHORT WAVE TROUGH OVER SOUTH DAKOTA NEARS THE REGION. BY
OVERNIGHT THE LOW-LEVEL INFLUENCE OF THIS WILL HELP INCREASE
700-925MB MOISTURE TRANSPORT ENDING THE DRY AIR SUPPRESSION AND
LIKELY LEADING TO A BLOSSOMING OF SNOW FROM NORTHWEST TO SOUTHEAST
OVERNIGHT. THERMAL PROFILES SUPPORT SNOW FROM THE GET GO AND
ATTENTION HAS BEEN ON KEYING IN HOW PERSISTENT AND WHERE MESOSCALE
FORCING WILL INDUCE A BAND OF SNOW ON MONDAY MORNING. CONCEPTUALLY
THIS TYPE OF PACIFIC SYSTEM...WITH ALMOST A CLIPPER NATURE AS IT
COMES IN TOMORROW MORNING...WOULD HAVE A FRONTOGENETIC
ENHANCEMENT WITHIN ITS FOCUSED BUT DEEP VERTICAL MOTION. GIVEN
CURRENT OBSERVATIONAL TRENDS ALREADY ALONG THAT BAROCLINIC ZONE
WITH JUST A LEAD PERTURBATION...AND THE FORECAST OF NEGATIVE EPV
/ INSTABILITY FROM MOST GUIDANCE...THERE SHOULD BE NO PROBLEM
HAVING MODERATE SNOW DURING THE MORNING COMMUTE...WITH AN AREA OF
TEMPORARY HEAVY SNOWFALL RATES POSSIBLE. THE CHALLENGE IS KEYING
IN ON HOW FAR EAST AND SOUTH THAT HEAVIER SNOW EXTENDS AND HOW
LONG. FOR RIGHT NOW HAVE NORTH CENTRAL IL MOST FAVORED IN DURATION
BUT LIKELY AT LEAST SOME HEAVY BURSTS EXTENDING EAST INTO A PART
OF THE CHICAGO METRO.
MIXING RATIOS OF 2 TO 3 G/KG ON LIFTED LAYERS LOOK TO OFFSET NOT-
THE-BEST THERMAL PROFILE FOR EFFICIENT RATIOS. IN THE FORECAST WE
HAVE THIS SUPPORTING TOTAL SNOWFALL AMOUNTS OF 2 TO 3.5 INCHES IN
MUCH OF NORTH CENTRAL IL WHILE 1 TO 2 INCHES ACROSS MUCH OF THE
REST OF THE AREA...WITH RATES AT TIMES ENOUGH TO OFFSET THE MILD
PAVEMENT TEMPERATURES /UPPER 40S TO MID 50S/. THE EXCEPTION WOULD
BE THE FAR SOUTH WHERE RATIOS LOOK TO BE QUITE LOW AND
TEMPERATURES MONDAY MORNING SHOULD BE SEVERAL DEGREES ABOVE
FREEZING...POSSIBLY EVEN YIELDING A MIX FROM PONTIAC TO FOLWER AND
SOUTHWARD.
FOR RIGHT NOW HAVE FELT MOST COMFORTABLE GIVEN FORECAST SNOWFALL
RATES AND TOTAL SNOWFALL AMOUNTS TO ISSUE A WINTER WEATHER
ADVISORY FOR THE ROCKFORD AREA AND ADJACENT COUNTIES...WHILE
HITTING THE REMAINDER OF THE AREA WITH A SPECIAL WEATHER
STATEMENT. IT IS CERTAINLY POSSIBLE THE ADVISORY WILL NEED TO BE
EXPANDED FOR A CORRIDOR EAST-SOUTHEASTWARD GIVEN THE TIME OF DAY
WHICH SNOW WILL OCCUR...BUT OBSERVATIONAL TRENDS OF UPSTREAM
SNOWFALL RATES COMPLIMENTING FURTHER SHORT RANGE GUIDANCE...WILL
BETTER ENABLE THE EVENING SHIFT TO MAKE THAT DECISION IF
NECESSARY.
ANY PRECIPITATION BY EARLY MONDAY AFTERNOON SHOULD BECOME LIGHT
AND SHIFTING SOUTHEAST...WITH THERMAL PROFILES INDICATING THE
POSSIBILITY OF SOME LIGHT DRIZZLE/RAIN AS SATURATION IS LOST IN
THE ICE NUCLEATION LAYER.
LOOKING AHEAD TO TUESDAY INTO TUESDAY NIGHT...NCEP MODEL GUIDANCE
HAS ACTUALLY TRENDED BACK A LITTLE QUICKER WITH THE PRECIP SPREAD
INTO THE AREA TUESDAY AHEAD OF AN IMPRESSIVE WAVE...WHICH WILL
ACQUIRE A NEGATIVE TILT AS IT MOVES OVER THE AREA TUESDAY NIGHT.
CONTINUE TO EASE RAIN SHOWERS NORTHEASTWARD DURING THE DAY CLOSER
TO THE EC...BUT IF THIS TREND CONTINUES THAT MAY NEED TO BE SPED
BACK UP. THE CHANCES FOR MORE RAINFALL AND CONVECTIVE CHANCES WILL
REMAIN FOCUSED ON TUESDAY NIGHT AS THE ELEVATED LAPSE RATES
STEEPEN AND PWATS SHARPLY INCREASE. RAINFALL AMOUNTS IN EXCESS OF
ONE HALF INCH LOOK PLAUSIBLE OVER THE AREA...ESPECIALLY IF
THUNDER COVERAGE IS MORE THAN SCATTERED.
TEMPERATURES LOOK TO CONTINUE BELOW NORMAL THROUGH TUESDAY...WITH
RISING TEMPERATURES TUESDAY NIGHT.
&&
.LONG TERM...
300 PM CDT
WEDNESDAY THROUGH SUNDAY...
LONG TERM...WEDNESDAY THROUGH SATURDAY...
THE INITIAL CONCERN WILL BE STRONG SOUTHWEST WINDS AS THE STRONG LOW
MOVES FROM SOUTHERN WISCONSIN TO GEORGIAN BAY ON WEDNESDAY. LOW
INTENSITY LOOKS TO BE PEAKING WEDNESDAY MORNING WITH THE LOW JUST
NORTH OF THE CWA WITH A SLIGHT WEAKENING AS IT TRACKS ACROSS
NORTHERN LAKE MICHIGAN. THIS WILL BE A GOOD STRONG WIND SET UP
ACROSS THE AREA...ESPECIALLY NORTHERN SECTIONS. FORECAST SOUNDINGS
CONTINUE TO SHOW DIFFERENCES IN SPEEDS THROUGH THE LOWEST FEW
THOUSAND FEET OF THE ATMOSPHERE BUT EVEN THE LOWER END GUIDANCE
SHOWS 30+ KT GUST POTENTIAL STARTING EARLY WEDNESDAY MORNING. IN
ADDITION...SOME RAIN SHOWERS AND ISOLATED THUNDER MAY LINGER ACROSS
NORTHERN AREAS FIRST THING WEDNESDAY MORNING BEFORE DRIER AIR TAKES
OVER. HIGHS WILL BE QUITE A BIT WARMER WITH HIGHS IN THE 50S NORTH
AND PROBABLY 60S SOUTH. A LESS FOCUSED UPPER TROUGH WILL KICK
ANOTHER SURFACE LOW FROM THE SOUTHERN PLAINS UP THE OHIO VALLEY AND
TO NORTHERN NEW ENGLAND THURSDAY. THIS LOW WILL PASS TO THE SOUTH OF
THE AREA WEDNESDAY EVENING BRINGING SHOWER CHANCES TO THE SOUTHERN
HALF OR SO OF THE AREA. A DEEPER UPPER TROUGH WILL THEN PIVOT ACROSS
THE PLAINS AND GREAT LAKES THURSDAY BRINGING A COLD FRONT ACROSS THE
AREA THURSDAY MORNING...WITH SOME PRECIP POTENTIAL WITH THE UPPER
TROUGH PASSAGE LATER IN THE DAY. STRONG HIGH PRESSURE WILL MOVE FROM
CENTRAL CANADA TO THE CENTRAL AND SOUTHERN PLAINS INTO SATURDAY WITH
MUCH COLDER AIR RETURNING TO THE AREA. WILL PROBABLY ONLY SEE HIGHS
IN THE 30S FRIDAY AND NEAR 40 SATURDAY. LIGHT LAKE EFFECT PRECIP MAY
OCCUR ACROSS ACROSS FAR NORTHEAST ILLINOIS AND NORTHWEST INDIANA
FRIDAY.
THE LONGWAVE UPPER TROUGH WILL DEEPEN ACROSS THE EASTERN U.S. WHILE
SHARP RIDGING BUILDS WEST LATE IN THE WEEK. AN UPPER TROUGH LOOKS TO
MOVE SOUTHEAST FROM THE NORTHERN PACIFIC SHUNTING THE RIDGE EAST
INTO SUNDAY WHICH MAY BRING A WARM UP BUT WELL ORGANIZED LOW
PRESSURE IS EXPECTED TO CROSS THE AREA LATER SUNDAY ULTIMATELY
EVOLVING INTO ANOTHER DEEP LONGWAVE TROUGH OVER THE EASTERN U.S. SO
WARMING MAY END UP BEING SHORT LIVED.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* EAST-NORTHEAST WINDS 10-15 KT THOUGH PERIOD WITH A FEW HIGHER
GUSTS POSSIBLE OVERNIGHT.
* SNOW DEVELOPING 09-11Z WITH IFR/LIFR CONDITIONS EXPECTED
12-17Z.
* SNOW MAY MIX/CHANGE TO LIGHT FREEZING DRIZZLE/DRIZZLE LATE
MONDAY MORNING BEFORE ENDING.
RATZER
//DISCUSSION...UPDATED 03Z...
NARROW BAND OF SNOW ALONG ELEVATED WARM FRONTAL ZONE REMAINS JUST
OFF TO THE NORTH/NORTHEAST OF TERMINALS LATE THIS EVENING...AND
HAS WEAKENED SINCE EARLIER. A FEW FLURRIES POSSIBLE FROM SOUTHERN
PERIPHERY OF THIS FEATURE DURING REMAINDER OF LATE EVENING AND
EARLY OVERNIGHT HOURS...THOUGH WITH LITTLE IMPACT TO VIS. MID-
LEVEL DISTURBANCE OVER NORTHERN IA/MINNESOTA WILL MOVE EAST
OVERNIGHT AND WILL RESULT IN HEAVIER AND MORE WIDESPREAD SNOW
SPREADING ACROSS THE TERMINALS DURING PREDAWN HOURS AS INDICATED
PREVIOUSLY.
RATZER
PREVIOUS DISCUSSION FROM 00Z...
AREA OF LIGHT/MODERATE SNOW HAS BEEN OCCURRING THIS AFTERNOON FROM
SOUTHWEST WISCONSIN INTO NORTHEASTERN IL IN ASSOCIATION WITH
ELEVATED WARM FRONTAL THERMAL GRADIENT AND WEAK DISTURBANCE
PROPAGATING ACROSS THE REGION. EASTERLY LOW LEVEL WINDS HAVE
MAINTAINED FAIRLY DRY CONDITIONS IN LOW LEVELS ACROSS CHI METRO
TERMINALS...THOUGH SOUTHERN FRINGE OF RADAR IDENTIFIABLE SNOW BAND
HAS SLIPPED SOUTH INTO ORD AND EXTRAPOLATION OF RADAR TRENDS
INDICATES IN MAY CONTINUE TO AFFECT ORD WITH SOME LIGHT SNOW
THROUGH ABOUT 01Z. EXPECT THERE WOULD BE A LULL DURING THE MID-
LATE EVENING HOURS THEN...UNTIL MORE WIDESPREAD LIGHT SNOW
DEVELOPS DURING PREDAWN HOURS WITH MORE AMPLIFIED UPPER WAVE
COMING OUT OF WESTERN MINNESOTA. GENERAL TIMING OF REDEVELOPMENT
OF SNOW LOOKS TO BE 06-08Z AT RFD...08-10Z FOR CHICAGO. STRONGEST
FORCING AND THUS LOWEST CIG/VIS CONDITIONS LOOKS TO BE 10-14Z AT
RFD AND 12-16Z ACROSS CHICAGO TERMINALS. AS SNOW DIMINISHES LATE
MORNING/MIDDAY IT MAY BRIEFLY MIX WITH DRIZZLE/FREEZING DRIZZLE.
LINGERING MVFR CIGS WILL LIKELY CONTINUE MONDAY AFTERNOON.
EAST-NORTHEAST WINDS HAVE REMAINED IN THE 9-14 KT RANGE THIS
AFTERNOON AND THIS IS EXPECTED TO CONTINUE THROUGH MUCH OF THE
FORECAST PERIOD.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH IN WINDS THROUGH PERIOD.
* HIGH FOR SNOW BY EARLY MONDAY MORNING...MEDIUM FOR DETAILS OF
CIG/VIS AS WELL AS EXACT START/END TIMES.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...RAIN SHOWERS DEVELOPING BY EVENING. CHANCE OF
THUNDERSTORMS. MVFR/IFR POSSIBLE. BREEZY SOUTHEAST WINDS.
WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR EARLY. GUSTY WEST-
SOUTHWEST WINDS.
THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE.
FRIDAY...SLIGHT CHANCE OF SNOW SHOWERS AND MVFR EARLY.
SATURDAY...VFR.
RATZER
&&
.MARINE...
248 PM CDT
A HIGH PRESSURE RIDGE EXTENDS FROM NORTHERN
MANITOBA AND ONTARIO TO THE LOWER GREAT LAKES LATE THIS AFTERNOON.
NORTHEASTERLY WINDS WILL BE IN PLACE TONIGHT AND STEADILY TURN
EASTERLY MONDAY MORNING AS THE CENTER OF THE HIGH MOVES TO NORTHERN
LAKE HURON. THE HIGH WILL CONTINUE TO THE EAST ALLOWING WINDS TO
TURN SOUTHEASTERLY INTO MONDAY NIGHT. ATTENTION TURNS TO LOW
PRESSURE THAT WILL BE DEVELOPING IN THE LEE OF THE ROCKIES MONDAY
NIGHT THEN CONSOLIDATE AND STRENGTHEN ACROSS THE SOUTHERN PLAINS
TUESDAY EVENING. THE LOW WILL THEN LIFT NORTHEAST ACROSS EASTERN
IOWA AND THEN NORTHERN LAKE MICHIGAN INTO WEDNESDAY AFTERNOON WHILE
MAINTAINING STRENGTH. SOUTH TO SOUTHEAST WINDS WILL INCREASE TUESDAY
NIGHT...WITH A MORE DUE EAST DIRECTION ACROSS THE NORTH. WINDS WILL
FLIP SOUTHWEST SOUTH OF THE LOW TRACK AND REMAIN EAST TO NORTHEAST
TO THE NORTH ON WEDNESDAY. WARMER AIR WILL BE BUILDING IN SO A SHARP
STABLE LAYER WILL DEVELOP LIMITING WIND GUST POTENTIAL. STILL EXPECT
30 KT ON THE OPEN WATERS BUT WITH MIXING SPREADING OFFSHORE
NEARSHORE AREAS COULD EASILY SEE MID TO HIGH END GALES. THINGS
SETTLE DOWN WEDNESDAY NIGHT WHILE ANOTHER WEAKER LOW MOVES UP THE
OHIO VALLEY BUT STRONG HIGH PRESSURE WILL BUILD IN BEHIND IT. THIS
WILL BRING A SHIFT TO NORTH TO NORTHWEST WINDS ACROSS THE LAKE
THURSDAY WITH COLDER AIR ALLOWING MIXING TO DEEPEN AND BRINGING THE
POTENTIAL FOR A PERIOD OF LOWER END GALES. THE HIGH WILL MOVE
SOUTHWARD INTO THE PLAINS KEEPING WINDS NORTHERLY BUT ALLOWING
SPEEDS TO SLACKEN THROUGH THE END OF THE WEEK AND INTO THE WEEKEND.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008...3 AM MONDAY TO
NOON MONDAY.
IN...NONE.
LM...NONE.
&&
$$
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
834 PM CDT Sun Mar 22 2015
.UPDATE...
ISSUED AT 825 PM CDT SUN MAR 22 2015
Shortwave that will bring a wintry mix to parts of our area Monday
morning was pushing across central North Dakota with a lead wave
seen on the water vapor loop tracking into northwest Iowa. Narrow
band of frontogenetical forcing snows that occurred well to our
north late this afternoon into early this evening continuing to
to hold its position roughly from LaCrosse to Chicago. Latest
HRRR model suggests precip will start to push into our northern
areas between 07z-10z with RAP soundings indicating most of the
area to see surface temps above freezing, but barely, north of
I-74, when the precip starts to move in. However, there will be
enough evaporative cooling to see some sleet and possibly snow
to mix in at times initially, especially across our northern
counties where the low levels cool off significantly enough to
bring about the threat for more of a sleet-snow mixture. Further
south, the better lift doesn`t arrive until mid-morning and by
then surface temperatures should be warm enough to support some
light rain showers, which may mix with a little sleet at the
start. All in all, it looks as if areas along and north of the
I-74 corridor may see the mix move in just before the morning
rush so there may be some slick spots to deal with on the way
to work or school tomorrow morning.
Have made some minor adjustments to the forecast for the rest of
the evening hours, especially with the early evening temperatures
and precip timing for late tonight. Should have the updated zones
out by 900 pm.
&&
.SHORT TERM...(Tonight)
ISSUED AT 308 PM CDT SUN MAR 22 2015
Main forecast concern for this part of the forecast is with timing
of precipitation later tonight, and placement of any mixed precip.
Narrow band of light snow has been tracking from south central
Minnesota southeast into the Chicago area this afternoon. This has
been occurring along a baroclinic zone near a developing 850 mb warm
front. This thermal gradient will be slipping southward overnight,
as additional precipitation develops in response to a shortwave
currently pushing across South Dakota. Latest model trends have been
to slow the arrival of this precipitation in our area a bit,
reaching the Peoria area between 4 and 7 am. Forecast soundings
there showing a tongue of warm air around 800 mb reaching +2 to +3C
depending on the model, but quite a bit of dry air still present
below that, indicating potential for sleet. Any rain mixed in
initially will probably start to transition more toward snow as the
column aloft moistens and ice crystals are produced in the -10C to
-20C layer. Temperatures will be very close to freezing north of the
I-74 corridor, so will need to watch for any freezing rain potential
as well, but given the warmer ground temperatures as of late, the
icing threat would be more toward elevated surfaces. Additionally,
snow/sleet accumulation should be minimal as well. Arrival of the
precipitation further south along the I-72 corridor would likely not
be until after sunrise.
&&
.LONG TERM...(Monday through Sunday)
ISSUED AT 308 PM CDT SUN MAR 22 2015
Low pressure system moving into the upper Mississippi Valley area as
of Sunday afternoon, will track across northern IL and southern WI
Monday continuing to spread precipitation across central IL through
Monday afternoon. With lingering cold air near the surface and a
warm layer of southwesterly flow at 850 mb (~5000 ft), there will be
potential for a mix of winter precipitation. The warm layer aloft
looks sufficient to melt snow aloft to just north of the I-74
corridor, while surface/near surface temperatures below freezing
extend to just south of the I-74 corridor so this area will be
subject to mixed precipitation into early afternoon Monday.
Initially, sleet, snow and some potential for freezing drizzle early
in the morning, then mainly rain, and sleet into the early afternoon
as surface temperatures rise. Highs should eventually reach around
40 north of I-74 ranging up to the low 50s from Jacksonville to
Lawrenceville.
As the first clipper system exits central/SE IL late Monday evening,
another chance of rain showers arrive by overnight Monday night
ahead of a warm front associated with a low pressure system
approaching via the central Plains. Warm sector associated with this
low will bring modest values of CAPE and strong bulk shear late
Tuesday afternoon into Tuesday evening, although values still not
consistent model to model. Strongest convective potential appears to
be Tuesday afternoon over Missouri, but this activity could spread
into west central IL. SPC Day 3 severe weather outlook for Tue
afternoon/evening has a marginal risk for severe thunderstorms with
large hail/severe winds into our SW counties of Schuyler, Scott,
Morgan and Cass during Tue evening.
Forecast models continue to advertise diminishing chances for
precipitation Wed. as the system shifts E/NE of central IL. Breezy
WSW winds and partial clearing expected along with highs reaching
the upper 50s to mid 60s, which will be the warmest day of the week.
The 00Z extended forecast models continue to show strong upper level
trough digging southward into the Midwest Thursday and Friday
bringing mostly cloudy skies and a few light rain and snow showers
Thu night into Fri morning. This will bring much colder temperatures
with highs in upper 40s/lower 50s Thu and only in the upper
30s/lower 40s Friday. Temps slowly modify during the weekend with
highs in the 50s by Sunday. GFS and ECMWF models show an upper level
closed low moving into the western great lakes Sunday and returning
chance of rain, or possibly snow showers to central IL.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
ISSUED AT 612 PM CDT SUN MAR 22 2015
VFR conditions expected thru 10z at PIA and about 12z at BMI
before a mix of rain, sleet and snow move in from the northwest.
At that time, expect cigs to go to MVFR across our northern TAF
sites with bases in the 1500-2500 foot range. Further south, as
the light precip shifts into SPI, DEC and CMI, expect mostly
light rain and possibly some sleet to develop, but current short
term models start to show some weakening trends and for that
reason will continue to hold with VCSH at this time to see what
the later models show with respect to how long the precip will
hold together as it tracks southeast on Monday. At any rate,
main concern further north will be during the 10z-16z time frame
as surface temperatures will be close to the freezing mark. As
the precip develops, we may see enough evaporative cooling take
place to bring temperatures briefly below freezing for a time
Monday morning, which may create some slick spots.
Surface winds will remain out of a mostly easterly direction thru
this forecast period with speeds in the 10 to 15 kt range with a
few gusts around 20 kts, especially as the precip approaches our
northern TAF sites early Monday morning, with the gusts expected
to hold thru much of the day, especially along and north of the
I-74 corridor.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1005 PM CDT Sun Mar 22 2015
.UPDATE...
Issued at 1005 PM CDT SUN MAR 22 2015
The latest NAM and RAP forecast soundings are less bullish with
the mid level moisture than earlier progs, and this may be the
reason why elevated storms have failed to form along the boundary.
The 00Z RAOB from TOP and OAX show there is still quite a bit of
moistening to take place and there is an AC deck behind the front.
However there has not been much development in these clouds and
with no real large scale forcing to lift parcels, think
convergence along the boundary from the low level jet is the only
mechanism to get storms to go. This convergence has not been
strong enough to this point for storms that developed earlier to
maintain an updraft. With model progs veering the low level jet to
the southwest and west, this convergence should weaken. With all
of this in mind, have paired back the slight chance pops to the
northeast corner of the forecast area. Any storm is likely to be
high based and may not even produce measurable precip with the
MUCAPE being very limited if there is any at all.
&&
.SHORT TERM...(This Evening through Monday)
Issued at 232 PM CDT SUN MAR 22 2015
A weak shortwave in the northwest flow aloft will track over the
upper Midwest this evening and overnight. This will drag a cold
front through the area, which is currently located in NW KS and
central NE. Ahead of the front low level moisture advection has
worked into central KS this morning as evident by the cumulus field
that has developed. This will inhibit how low the dew points mix out
in that region, while further east the dew points mix out much lower
into the 30s. There is decent agreement on the timing of the front,
which should enter north central KS around sunset. As the front
moves southeastward into the slightly better moisture an isolated
shower may develop along the front. There will be a decent amount of
dry air closer to the surface which may make it difficult for
precipitation to accumulate much over a few hundredths. With this
increased moisture the elevated cape overnight should range from
300-500 j/kg, therefore can not rule out the possibility of some
thunder. If the showers can develop it will be brief as the front
continues to progress eastward, and dry air moves behind the front
in the 900-850 MB layer. The highest chance are across far northeast
and east central KS.
This front is forecast to stall out in far southern KS tomorrow
morning. Overnight low temperatures will range from the upper 40s in
southeast KS to the upper 30s in north central KS. Cooler air moving
in behind the front places highs tomorrow in the 60s. During the day
tomorrow a shortwave will track over the central Rockies and
eventually the central plains overnight. Increased southerly flow
ahead of the wave lifts the front back to the north. Also, an
increasing low level jet advects higher moisture from the south into
southern KS. This higher moisture should help to erode the cap along
and north of the warm front. Showers and thunderstorms will increase
in coverage in the late afternoon and early evening.
.LONG TERM...(Monday Night through Sunday)
Issued at 232 PM CDT SUN MAR 22 2015
Monday Night - Thunderstorm coverage will increase through the
evening and overspread the area through the night. This will be in
response to a strong low level jet bringing quick moisture
advection, warm air advection, and enhanced isentropic ascent
underneath a plume of fairly steep mid level lapse rates. A broad
area of mid/upper level forcing will also overspread the area
during the evening and overnight hours. The moisture influx into
the region will be nearly continuous, as will storm development,
but the focus area for development will gradually shift to the
north and east and should exit the forecast area near or shortly
after sunrise on Tuesday. MUCAPE is likely to exceed 1000 J/kg at
times with strong mid/upper flow supportive of some elevated
supercell structures and large hail associated with a few of these
storms. Pockets of heavy rainfall will also be possible with the
continued storm development through the night.
Tuesday - The weather scenario on Tuesday remains complex but at
least most model guidance is beginning to resolve low level
features that fit the conceptual model of this type of strong
negatively tilted short wave trough. The upper short wave is still
forecast to deepen sharply during the day on Tuesday as the heart
of the trough tracks from SW Colorado into far southeast NE. A
strong mid level jet max will track along the southern periphery
of the trough, and expect surface low pressure to translate from
SW Kansas into NW Missouri. The NAM is a notable outlier in the
track of the surface low and tracks it south of the forecast area
(although still pulling south winds and higher dewpoints well
north into the forecast area with another weak sfc low a bit
farther northwest. Moisture return will be efficient on Monday
night into Tuesday ahead of this system, but the moisture source
will be modified continental air so looking at max dewpoints only
in the mid to perhaps upper 50s in the warm sector. Expect to see
at least some partial clearing and warming in the warm sector in
SBCAPE may exceed 1000 J/kg. Deep layer wind shear will be very
strong, and if storms develop they should quickly obtain supercell
structure as they move quickly to the east. Given the strong
dynamics with this storm system, it would now make sense for
storms to develop a bit earlier in the afternoon along the dry
line and under the rapid mid level cooling associated with the
upper trough. Feel that the ECMWF (which is quite similar to the
GFS and GEM) rendition of thunderstorm initiation occurring in the
local forecast area with some strengthening and organization
possible as they cross eastern KS near/south of the surface low
track. So, will re-introduce the potential for some strong to
severe thunderstorms for a few hours during the early/mid
afternoon on Tuesday with hail and damaging winds the main
hazards in the local forecast area. Aside from the warm sector,
elevated instability remains in place north of the surface low
track as well, and will likely support scattered showers and a few
thunderstorms as the system moves through. With the very strong
trough aloft, there may be some chance for a bit of hail even
north of the low. It now appears that the driest air behind the
system may remain just south and west of the area, so while it
will be windy late Tuesday the RH may remain above critical levels
locally and likely rainfall on Monday night could limit the fire
danger.
Tuesday night - Saturday - This system moves quickly northeast and
out of the area and expect dry conditions after sunset on Tuesday.
Wednesday will still be fairly warm but another strong upper
trough will dive across the Plains from the northwest with a much
cooler airmass moving in with it. Depending on airmass moisture in
place in advance of this system, there could be scattered showers
with the front passage late Wednesday. Temperatures then become
much cooler and there appears to be some strong potential for a
freeze...and perhaps a hard freeze...Friday morning and Saturday
morning. Currently have lows in the upper 20s but if skies are
clear on Saturday morning and the surface high is perfectly timed,
could end up in the low to middle 20s. The recent warm
temperatures may increase the impacts of a hard freeze but will
have to look deeper into this and how far along the growing season
is at this time. Warmer temperatures are then in store again for
next weekend.
&&
.AVIATION...(For the 00Z TAFs through 00Z Monday Evening)
Issued at 1005 PM CDT SUN MAR 22 2015
Have removed the mention of VCTS as it looks increasingly unlikely
for storms to impact the terminals tonight. VFR conditions should
prevail with winds shifting to the northwest and north behind the
front.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Wolters
SHORT TERM...Sanders
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS JACKSON KY
942 PM EDT SUN MAR 22 2015
.UPDATE...
ISSUED AT 942 PM EDT SUN MAR 22 2015
DID A MINOR UPDATE TO TWEAK THE HOURLY T AND TD GRIDS PER THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
UPDATE ISSUED AT 645 PM EDT SUN MAR 22 2015
BUMPED UP SKY COVER TO BETTER REFLECT CURRENT CONDITIONS...AND
ALIGNED TEMPS/DEW POINTS WITH MOST RECENT OBS. KEEPING ON EYE ON
SOME LIGHT RADAR RETURNS...BUT CURRENT THINKING IS THAT ANY
MEASURABLE PRECIP WILL STAY SOUTH OF THE AREA TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 400 PM EDT SUN MAR 22 2015
19Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING IN FROM THE NORTH
WITH LOW PRESSURE SKIRTING THE BOUNDARY JUST TO OUR SOUTH. ON
RADAR...LIGHT RETURNS KEEP TRYING TO SNEAK ACROSS OUR BORDER WITH
TENNESSEE...BUT SO FAR THERE HAVE NOT BEEN ANY OBS OR REPORTS OF
ANYTHING REACHING THE GROUND IN KENTUCKY. THICKENING HIGH CLOUDS
ARE SEEPING NORTH ASSOCIATED WITH THE SOUTHERN SYSTEMS...BUT ONLY
RECENTLY HAVE THE CLOUDS GOTTEN OPAQUE ENOUGH TO BLOCK THE SUN.
WITH THE FILTERED SUNSHINE...TEMPERATURES WERE ABLE TO CLIMB INTO
THE LOW 60S ACROSS THE SOUTH AND THE MID 50S TO THE NORTH.
DEWPOINTS BASICALLY HELD STEADY THROUGH THE DAY SO THAT THEY STILL
VARY FROM THE UPPER 20S IN THE NORTH TO LOW 40S IN THE SOUTH.
MEANWHILE...WINDS REMAIN MAINLY FROM THE NORTHEAST AT 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK SOUTHERN STREAM TROUGH PASSING THROUGH THE
DEEP SOUTH WHILE SOME ENERGY SLIPS INTO THE OHIO VALLEY LATE
MONDAY IN THE NORTHERN STREAM. HEIGHTS WILL GRADUALLY RISE THROUGH
TUESDAY MORNING AS THE SOUTHERN TROUGH DEPARTS...EVEN WITH THE
NORTHERN ENERGY SCRAPING BY MONDAY NIGHT. GIVEN THE GENERAL MODEL
AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX
DETAILS THROUGH THE SHORT TERM.
SENSIBLE WEATHER WILL FEATURE THE SMALL POTENTIAL FOR SPRINKLES OR
LIGHT RAIN IN FAR SOUTHERN PARTS OF THE CWA TONIGHT. OTHERWISE
PARTLY TO MOSTLY CLOUDY SKIES WILL DOMINATE HELPING TO KEEP THE
LID ON THE WORST OF THE COOLING OVERNIGHT. FOR MONDAY...HIGH
CLOUDS WILL CONTINUE TO PLAGUE THE AREA AS WE WILL BE BETWEEN THE
SYSTEMS ON OUR FRINGES. LATER THAT NIGHT THERE WILL BE A SMALL
CHANCE FOR RAIN IN THE NORTHERNMOST PARTS OF EASTERN KENTUCKY AS
A DEVELOPING...BUT MOSTLY DRY...WARM FRONT LIFTS THROUGH THE
AREA.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS
INTO MONDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD.
AS FOR POPS...ENDED UP IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 335 PM EDT SUN MAR 22 2015
AN UPPER LEVEL TROUGH DIGGING INTO THE NORTHERN PLAINS WILL DRIVE A
WARM FRONT NORTHWARD ACROSS OUR AREA ON TUESDAY. WHILE MOISTURE IS
MEAGER WITH THIS FRONT...MODELS CONTINUE TO INDICATE THE POTENTIAL
FOR A FEW SHOWERS. THIS WARM FRONT WILL SHIFT NORTH OF OUR AREA
TUESDAY NIGHT. A WEAKENING SFC COLD FRONT ASSOCIATED WITH LOW
PRESSURE OVER THE GREAT LAKES WILL DROP DOWN ACROSS THE AREA ON
WEDNESDAY WHILE THE SUPPORTING UPPER LEVEL TROUGH EVENTUALLY OUT
RUNS ALL OF ITS SFC FEATURES. WHILE MOISTURE REMAINS MEAGER WITH
THIS SYSTEM...ISOLATED TO SCATTERED SHOWERS AND PERHAPS A STRAY
THUNDERSTORM CAN NOT BE RULED OUT DURING THE DAY WEDNESDAY.
ANOTHER MORE SUBSTANTIAL...DEEPER TROUGH WILL REENERGIZE THE
BOUNDARY LEFT IN PLACE ACROSS THE REGION WEDNESDAY NIGHT INTO
THURSDAY. THERE WILL BE ENOUGH ENERGY WITH THIS SECOND UPPER TROUGH
THAT WE CAN EXPECT NUMEROUS SHOWERS TO DEVELOP ACROSS OUR AREA AS
ITS INDUCED SFC LOW DEVELOPS AND PUSHES UP THE MID MISSISSIPPI...
LOWER OHIO VALLEY. THIS WILL ALLOW THE SFC FRONT TO REORGANIZE AND
BEGIN ITS PUSH EASTWARD AGAIN. SFC BASED INSTABILITY DOES NOT LOOK
AS IMPRESSIVE BUT SHOULD BE ENOUGH TO KEEP MENTION OF A FEW
THUNDERSTORMS IN THE FORECAST. WHILE THE ENDS GENERALLY REMAIN THE
SAME WITH RESPECT TO SENSIBLE WEATHER...BOTH THE GFS AND ECMWF ARE
IN DECENT AGREEMENT WITH THIS SCENARIO...THE GFS DOES APPEAR MORE
AGGRESSIVE AND WELL DEFINED WITH ALL THE SFC FEATURES THAN THE
ECMWF. IN ADDITION...MODELS SEEM TO BE TRENDING A BIT SLOWER
OVERALL WITH THE EVOLUTION OF THIS PHASE OF THE EXTENDED.
IN ADDITION...OUR PATTERN TURNS MUCH COLDER FROM THURSDAY NIGHT INTO
THE WEEKEND AS A LARGE CANADIAN SFC HIGH PRESSURE SYSTEM SETTLES
OVER THE REGION. UPPER LEVEL ENERGY CONTINUES TO DIG IN FROM THE
NORTHWEST...DEEPENING THE TROUGH OVER THE OHIO AND TENNESSEE
VALLEYS. DEEPER MOISTURE WILL EXIT WITH THE FRONT BY THURSDAY
NIGHT...BUT AN UNSTABLE BOUNDARY LAYER WILL REMAIN IN PLACE AS THE
CORE OF THE TROUGH SWINGS THROUGH ON FRIDAY. WITH STEEP LAPSE
RATES...A FEW RAIN SHOWERS CAN NOT BE RULED OUT. IF FREEZING LEVELS
DROP LOW ENOUGH WE COULD EVEN SEE SOME WET SNOW MIX IN OVER THE
HIGHER TERRAIN. STILL SOME UNCERTAINTY IN THE MODELS WITH THE AMOUNT
OF MOISTURE AND COLD AIR COMING IN...BUT THERE SEEMS TO BE A GENERAL
CONSENSUS OF H850 TEMPS DROPPING TO AROUND -10C OVERHEAD BY SATURDAY
MORNING. THIS COULD RESULT IN A WIDESPREAD FREEZE SATURDAY MORNING
IF SFC HIGH PRESSURE BECOMES MORE CENTERED OVER EASTERN KENTUCKY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 645 PM EDT SUN MAR 22 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. A SURFACE HIGH
PUSHES SOUTH TONIGHT AND INTO MONDAY AS LOW PRESSURE SCOOTS PAST
TO THE SOUTH. HIGH CLOUDS OF VARYING OPACITY FROM THE SOUTHERN LOW
WILL COVER THE REGION DURING THIS TIME. WINDS THROUGH MUCH OF
THE TAF PERIOD WILL REMAIN GENERALLY LIGHT FROM THE NORTH TO
NORTHEAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...GREIF
LONG TERM...ABE/RAY
AVIATION...JVM/GREIF
AREA FORECAST DISCUSSION...RESENT
NWS JACKSON KY
320 PM EDT SAT MAR 21 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 320 PM EDT SAT MAR 21 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE NOSING DEEPER INTO EAST
KENTUCKY KEEPING THE SKIES MOSTLY CLEAR...ASIDE FROM A SOME HIGH
CLOUDS SEEPING NORTH FROM LOW PRESSURE WELL TO THE SOUTHWEST OF
THE AREA. DESPITE THE HIGH PRESSURE AND RETURNING SUNSHINE...
DEWPOINTS REMAIN IN THE UPPER 30S AND LOWER 40S KEEPING THE RH
AROUND 50 PERCENT FOR MUCH OF THE AREA. MEANWHILE...TEMPERATURES
ARE STILL CATCHING UP TO FORECAST HIGHS WITH A COUPLE OF HOURS OF
CLIMBING YET TO GO...RANGING FROM LOW 60S IN THE SOUTH TO THE MID
50S IN THE NORTH. WINDS ARE GENERALLY LIGHT FROM THE SOUTHWEST...
THOUGH ON THE NORTHEAST FRINGE OF THE HIGH PRESSURE SYSTEM THERE
HAVE BEEN A FEW GUSTS TO BETWEEN 15 AND 20 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS THEY DEPICT SOUTHERN STREAM ENERGY
BRUSHING BY KENTUCKY SUNDAY INTO MONDAY AS A BROAD TROUGH SLOWLY
MOVES THROUGH THE LOWER MISSISSIPPI VALLEY AND DEEP SOUTH. DURING
THIS TIME...EASTERN KENTUCKY WILL BE IN THE MIDST OF GENERALLY
BENIGN NORTHWEST FLOW IN WHICH ANY NORTHERN STREAM ENERGY STAYS
OFF TO THE NORTHEAST OF THE AREA. HEIGHTS DO FALL A BIT TONIGHT
INTO SUNDAY...BUT NOT DRAMATICALLY ENOUGH TO HAVE MUCH IMPACT ON
SENSIBLE WEATHER. GIVEN THE MODEL AGREEMENT...HAVE FAVORED THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS THROUGH MONDAY
MORNING.
SENSIBLE WEATHER WILL FEATURE A COOL NIGHT DESPITE THE HIGH
CLOUDS DRIFTING IN FROM THE SOUTHWEST FROM A WEAK LOW NEAR THE
CENTRAL GULF COAST. AT THE SAME TIME...A COLD FRONT WILL SLIP
INTO AND THROUGH THE AREA WITH NOT MUCH IN THE WAY OF MOISTURE.
EXPECTING A DECENT START TO THE NIGHT FOR DECOUPLING AND
RADIATIONAL COOLING SO HAVE BROUGHT THE VALLEY TEMPS DOWN QUICKER
THAN THE MODELS WOULD SUGGEST. THE COLDER SPOTS MIX OUT IN THE
MORNING UNDER PARTIAL SUNSHINE SUNDAY WITH TEMPERATURES TOPPING
OUT A CATEGORY OR TWO BELOW TODAY/S HIGHS. WITH THE FRONT SOUTH OF
THE AREA FOR SUNDAY NIGHT WE WILL SEE SOME COLDER TEMPERATURES
ACROSS THE BOARD WITH SOME MINOR RIDGE TO VALLEY DIFFERENCES BY
DAWN. FOR TONIGHT...PATCHY FOG CAN BE EXPECTED IN THE VALLEYS
TOWARD DAWN WHILE ON SUNDAY NIGHT THERE MAY BE SOME PATCHES OF
FROST IN THE VALLEYS. HAVE LEFT THE FROST OUT OF THE ZFP FORECAST
FOR NOW...BUT DID ADD SOME TO THE GRIDS.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SUNDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD.
AS FOR POPS...KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 235 PM EDT SAT MAR 21 2015
THE UPCOMING WEEK WILL FEATURE A TRANSITION FROM MEAN ZONAL FLOW
EARLY IN THE PERIOD TO A HIGHLY AMPLIFIED PATTERN BY THE END OF THE
PERIOD...WITH A DEEP TROUGH BECOMING ESTABLISHED IN THE EASTERN
UNITED STATES WITH A RIDGE IN THE WEST. THIS WILL RESULT IN A
SIGNIFICANT COOL DOWN AS WE HEAD INTO NEXT WEEKEND.
THE START OF THE FORECAST PERIOD WILL FEATURE A SHORT WAVE MOVING
THROUGH THE SOUTHERN STREAM ACROSS THE SOUTHEAST U.S. AND THEN OFF
THE ATLANTIC COAST. A WEAK SYSTEM WILL ALSO BE PASSING BY TO OUR
NORTH. OTHER THAN INCREASED CLOUDINESS THERE SHOULD BE LITTLE IMPACT
TO OUR AREA FROM THESE SYSTEMS. AS WE MOVE INTO MID WEEK A MUCH MORE
SIGNIFICANT SHORT WAVE WILL EMERGE INTO THE PLAINS. OUT AHEAD OF
THIS...A SURFACE WARM FRONT WILL MOVE ACROSS THE REGION WITH A
SIGNIFICANT SURGE OF WARM AIR MOVING INTO THE AREA AHEAD OF AN
ADVANCING COLD FRONT. AS THE UPPER SYSTEM AND SURFACE LOW MOVE INTO
THE GREAT LAKES REGION THE COLD FRONT WILL MOVE INTO ERN KY
WEDNESDAY NIGHT INTO THURSDAY. THIS WILL BRING A GOOD CHANCE OF
RAIN...WITH COOLER TEMPERATURES FOLLOWING. HAVE DECIDED TO ADD A
SLIGHT CHANCE OF THUNDER WITH THIS FRONTAL PASSAGE AS WELL..WHICH
WILL BE IN GOOD AGREEMENT WITH WFOS TO OUR WEST AND SOUTH.
A SECOND SURGE OF COLDER AIR LOOKS TO IMMEDIATELY FOLLOW THE INITIAL
COLD FRONTAL PASSAGE...AND THE POSSIBILITY EXISTS FOR SOME SNOW TO
AT LEAST MIX IN WITH RAIN IF ANY PRECIPITATION LINGERS INTO FRIDAY
NIGHT. THE OPERATIONAL GFS IS THE MOST AGRESSIVE MODEL WITH THE COLD
AIR SURGE...WITH THE ECMWF AND GFS ENSEMBLE MEAN...WHILE STILL
COLD...NOT AS IMPRESSIVE...WITH 85H TEMPERATURES 5 DEGREES OR SO
WARMER. AT THIS POINT THERE IS STILL CONSIDERABLE UNCERTAINTY
REGARDING THE WEATHER DETAILS FOR THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 155 PM EDT SAT MAR 21 2015
NOW THAT THE LOW CLOUDS HAVE BROKEN UP VFR CONDITIONS WILL
DOMINATE THE FORECAST WITH THE ONLY CIGS EXPECTED TO BE ABOVE 20K
FEET THROUGH THE NIGHT. HAVE INCLUDED A TOUCH OF VALLEY FOG IN
THE GRIDS LATE TONIGHT AND ALSO ALLOWED SOME MVFR BR TO SLIP INTO
THE SME TAF SITE TOWARDS DAWN...OTHERWISE NO RESTRICTIONS. BREEZY
CONDITIONS ARE FOUND AT SYM THIS AFTERNOON WITH LIGHTER WINDS
ELSEWHERE...GENERALLY FROM THE SOUTHWEST. LOOK FOR ALL WINDS TO
DIE DOWN THIS EVENING WITH ONLY LIGHT AND VARIABLE ONES EXPECTED
THROUGH THE DAY SUNDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS PADUCAH KY
320 AM CDT SAT MAR 21 2015
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 320 AM CDT SAT MAR 21 2015
HIGH CLOUDS ARE STREAMING NORTHEAST ACROSS THE ENTIRE REGION
THIS MORNING..AND THAT IS LIKELY TO CONTINUE THROUGH THE DAY
TODAY. NOT SURE HOW MUCH IMPACT IT WILL HAVE ON TEMPERATURES...BUT
ESPECIALLY IN THE SOUTH WOULD NOT BE SURPRISED IF IT HELD READINGS
DOWN A FEW DEGREES. IN THE NORTH...THE 00Z MODELS ALL BRING A WEAK
COLD FRONTAL WIND SHIFT INTO THE REGION...AND THAT COULD ALSO
PRESUMABLY KNOCK TEMPERATURES DOWN A FEW DEGREES FROM PREVIOUS
FORECASTS. THE OZARK FOOTHILLS REGION WILL STILL SEE TEMPERATURES
AROUND 70...BUT ELSEWHERE KNOCKED HIGHS DOWN A FEW DEGREES CLOSER
TO THE CONSENSUS OF 00Z GUIDANCE.
THE 00Z MODELS CONTINUE TO OPEN UP AND PUSH THE BAJA UPPER LOW
EAST NORTHEASTWARD INTO THE MID-SOUTH BY 00Z MONDAY. THE 03Z
SREF...00Z CANADIAN...AND 00Z WRF ARW AND NMM MODELS ALL BRING
THE NORTHERN EDGE OF THE PRECIPITATION SHIELD RIGHT TO THE
SOUTHERN BORDER OF OUR AREA. INCREASED POPS TO NEAR 15 RIGHT ON
THE AR AND TN BORDERS...BUT KEPT OUR REGION DRY FOR LATE TONIGHT
THROUGH SUNDAY AND INTO SUNDAY EVENING. IT WILL NOT BE A SURPRISE
TO SEE SOME LIGHT RAIN EVENTUALLY GET INTO SOUTHEAST MISSOURI OR
WEST KENTUCKY IN THIS TIME FRAME...BUT THE EVIDENCE IS JUST NOT
GREAT ENOUGH TO WARRANT A POP AT THIS TIME.
AS THAT SYSTEM PUSHES FARTHER EAST...A DISTURBANCE IN THE
NORTHWEST FLOW ALOFT MAY ALLOW A FEW SHOWERS TO PUSH INTO
NORTHWEST PORTIONS OF THE AREA MONDAY. THIS SYSTEM IS LOSING ITS
SURFACE REFLECTION OVER THE PLAINS AND ANY SHOWERS THAT TRY TO
REACH OUR AREA WOULD LIKELY BE DRYING UP QUICKLY AND AMOUNT TO
NEXT TO NOTHING. DID INSERT A SLIVER OF A SLIGHT CHANCE ALONG I-64
IN SOUTHERN ILLINOIS JUST TO BE SAFE.
A STRONGER UPPER-LEVEL STORM SYSTEM WILL PUSH EASTWARD INTO THE
NORTHERN PLAINS BY 12Z TUESDAY. THE 00Z MODELS ARE IN AGREEMENT IN
PUSHING A WARM FRONT NORTHWARD INTO OUR REGION...AND DEVELOPING
SLIGHTLY NEGATIVE SHOWALTER INDICES ALONG AND NORTH OF IT
OVERNIGHT. A FEW ELEVATED SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE MAINLY OVER SOUTHERN ILLINOIS OVERNIGHT MONDAY NIGHT INTO
TUESDAY MORNING. SLIGHT CHANCE POPS SHOULD SUFFICE FOR NOW.
WITH PLENTY OF AT LEAST HIGH CLOUD COVER... AND SURFACE HIGH
PRESSURE BUILDING INTO THE REGION FROM LATE THIS AFTERNOON THROUGH
MONDAY...TEMPERATURES ARE TRENDING SLIGHT DOWNWARD FROM PREVIOUS
FORECASTS. AFTER HIGHS ABOVE NORMAL IN THE UPPER 60S TODAY...A
COOLING TREND IS EXPECTED THROUGH MONDAY. THIS WILL STILL KEEP
READINGS AT OR ABOVE NORMAL EACH AFTERNOON. LOWS WILL ALSO BE AT
OR ABOVE NORMAL THROUGH THE PERIOD. MONDAY NIGHT COULD BE QUITE
MILD WITH THE WARM FRONT AND PRESUMABLY QUITE A BIT CLOUD COVER.
.LONG TERM...(TUESDAY THROUGH SATURDAY NIGHT)
ISSUED AT 320 AM CDT SAT MAR 21 2015
THIS EXTENDED FORECAST PERIOD STARTS WITH THE BEGINNING INFLUENCE OF
A DEVELOPING AND NEGATIVELY TILTED SHORTWAVE MOVING LEE OF THE
ROCKIES INTO THE UPPER MIDWEST AND THE CENTRAL PLAINS. THE
DIFFERENTIAL VORTICITY FIELDS AND INCREASING MOISTURE ADVECTION FROM
THE GULF OF MEXICO SERVES TO ACTIVATE (LIGHT UP) THE BAROCLINIC ZONE
(ENHANCED WARM FRONTAL ZONE) ORIENTED ACROSS THE NORTHERN HALF OF
THE WFO PAH FORECAST AREA.
RECENT MODEL TRENDS THE LAST 24-48 HOURS INDICATE THAT A TRAIN OF
ENERGY (SHORTWAVES) FOLLOWING THE LEAD SHORTWAVE SERVE TO
DEEPEN/SLOW DOWN THE TROUGH WEDNESDAY AFTERNOON THROUGH THURSDAY
EVENING. THIS ENHANCES COLD AIR ADVECTION FROM THE UPPER MIDWEST,
TIGHTENING THE BAROCLINIC ZONE AND INCREASING FRONTOGENESIS OVER THE
MIDDLE AND UPPER MISSISSIPPI VALLEY WEDNESDAY AFTERNOON.
FOR WHAT SEEMS TO BE THE STORY OF THE WINTER SEASON, SOME OF THE
ENERGY IN THE NORTHERN U.S. DIVES DOWN TOWARD CALIFORNIA/NORTHERN
MEXICO, GENERATING A CLOSED LOW CIRCULATION. AS PREVIOUSLY MENTIONED
IN OTHER DISCUSSIONS, THIS LOW SERVES TO AID IN HEIGHT FALLS
UPSTREAM, ENHANCING AND SHARPENING THE TROUGH IN THE CENTRAL PLAINS
AS THE UPPER LOW SHEARS OUT OVER THE NORTHEAST U.S. THIS IN TURN
SLOWS THE OVERALL EXIT OF THE COLD FRONT THROUGH THE WFO PAH
FORECAST AREA AND LEADS TO MINOR-OVERRUNNING OF MOISTURE OVER THE
POST FRONTAL ZONE. THIS WILL KEEP A SMALL CHANCE FOR RAIN OVER THE
AREA THROUGH AT LEAST FRIDAY.
NUMERICAL MODEL SIGNALS STILL SUGGEST THAT THE STRONGEST FORCING,
HIGHEST PRECIPITABLE WATER VALUES, HIGHEST POPS WILL BE FOCUSED ON
WEDNESDAY AFTERNOON AND EVENING. THE GREATEST CONVECTIVE POTENTIAL
STILL LIES JUST BEFORE AND DURING THAT TIME PERIOD. A FURTHER
ASSESSMENT FOR ANY SEVERE OR NEAR SEVERE POTENTIAL WILL BE ADDRESSED
IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.AVIATION...
ISSUED AT 1112 PM CDT FRI MAR 20 2015
CONSIDERABLE HIGH CLOUDS OVERNIGHT. WINDS NOT ENTIRELY CALM
THROUGH 06Z. GUIDANCE SUGGESTS CALM BUT THE RAP 13KM SAYS IT MAY
NOT STAY THAT WAY (2-3 KTS AT TIMES). GIVEN BOTH FACTORS...WILL
LIMIT THE FOG MENTION. HIGH CLOUDS WILL PERSIST THROUGH SATURDAY
AS WELL WITH LIGHT WINDS CONTINUING...MAINLY WITH A SSW COMPONENT.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...SMITH
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 AM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 150 AM EDT SAT MAR 21 2015
QUICK UPDATE TO FRESHEN UP GRIDS WITH LATEST OBS AND TRENDS. DID
PUT DRIZZLE IN A BIT LONGER MAINLY ACROSS THE EAST AS RADAR
CONTINUES TO SHOW SOME LIGHTER RETURNS. OTHERWISE NO MAJOR
CHANGES NEEDED FOR THIS UPDATE.
UPDATE ISSUED AT 1105 PM EDT FRI MAR 20 2015
HOURLY GRIDS WERE UPDATED BASED ON RECENT RADAR AND OBSERVATION
TRENDS. AREAS OF DRIZZLE CONTINUE ACROSS THE RADAR PER OBS AND
RADAR IMAGERY GENERALLY SOUTH OF INTERSTATE 64 AND EAST OF
INTERSTATE 75. THIS SHOULD GRADUALLY DIMINISH AS THE MOISTURE
BECOMES SHALLOWER. PATCHY FOG IS STILL ANTICIPATED AND MAY BE
DENSE AT TIMES ON SOME RIDGES. CLOUDS SHOULD NOT SCATTER OUT UNTIL
AROUND DAYBREAK...EXCEPT PERHAPS IN THE FAR NORTHWEST.
UPDATE ISSUED AT 815 PM EDT FRI MAR 20 2015
AREAS OF DRIZZLE HAVE DEVELOPED WITH AN UPSLOPE COMPONENT ACROSS
THE REGION. THIS LOW LEVEL MOISTURE WILL BECOME SHALLOWER AS THE
NIGHT PROGRESSES...WHICH SHOULD END THE DRIZZLE...BUT LOW CLOUDS
WILL REMAIN. SOME PATCHY FOG IS ANTICIPATED AND THIS COULD BECOME
DENSE ON THE RIDGES THROUGH STRATUS BUILD DOWN. THIS THREAT WILL
CONTINUE TO BE MONITORED. LOW CLOUDS HAVE CLEARED ACROSS PARTS OF
WESTERN IL...FAR WESTERN KY AND TN...BUT IT WILL PROBABLY BE AFTER
SUNRISE BEFORE THE LOW CLOUDS BEGIN TO LIFT ACROSS EASTERN KY.
MODEL TIME HEIGHT SECTIONS AND FORECAST SOUNDINGS SUGGEST THE LOW
CLOUDS LINGERING PAST 8 AM ON SATURDAY IN MANY LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 310 PM EDT FRI MAR 20 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF
KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA.
THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME
POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW
CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE
RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID
TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN
THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A
DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A
SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON
WEST TO NORTHWEST WINDS OF 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS
EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE
NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL
HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN
BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A
BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY
AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE
ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO
SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY
MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER
RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT
TERM.
SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH
BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG
AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE
FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP.
IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN
ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED
THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE
NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS
WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND
PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA
SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN
LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL
RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY
NIGHT...DESPITE THE HIGH CLOUDS.
USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS
WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS
WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z
TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM EDT FRI MAR 20 2015
THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN
PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT
THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE
END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST
TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE
WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A
WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL
WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND.
IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY
TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST
U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM
SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN
IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH
AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A
STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE
OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A
COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE
GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION
CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS
TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN.
HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT
THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 125 AM EDT SAT MAR 21 2015
LOW CLOUDS AND DRIZZLE STILL HANGING IN AT MANY SITES TONIGHT.
AREAS OF DRIZZLE ARE EXPECTED TO CONTINUE TO SUBSIDE OVERNIGHT AS
DRIER AIR SLOWLY WORKS EAST. MOST SITES WILL STAY IFR OR MVFR
THROUGH MID MORNING AT THE LATEST BEFORE WE BEGIN TO SEE SKIES
SCATTER OUT FROM WEST TO EAST. VFR CONDITIONS RETURN FOR MUCH OF
THE END OF THE TAF PERIOD AS DRYER AIR CONTINUES TO WORK EAST.
LIGHT WEST WINDS WILL GENERALLY PREVAIL THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
125 AM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1105 PM EDT FRI MAR 20 2015
HOURLY GRIDS WERE UPDATED BASED ON RECENT RADAR AND OBSERVATION
TRENDS. AREAS OF DRIZZLE CONTINUE ACROSS THE RADAR PER OBS AND
RADAR IMAGERY GENERALLY SOUTH OF INTERSTATE 64 AND EAST OF
INTERSTATE 75. THIS SHOULD GRADUALLY DIMINISH AS THE MOISTURE
BECOMES SHALLOWER. PATCHY FOG IS STILL ANTICIPATED AND MAY BE
DENSE AT TIMES ON SOME RIDGES. CLOUDS SHOULD NOT SCATTER OUT UNTIL
AROUND DAYBREAK...EXCEPT PERHAPS IN THE FAR NORTHWEST.
UPDATE ISSUED AT 815 PM EDT FRI MAR 20 2015
AREAS OF DRIZZLE HAVE DEVELOPED WITH AN UPSLOPE COMPONENT ACROSS
THE REGION. THIS LOW LEVEL MOISTURE WILL BECOME SHALLOWER AS THE
NIGHT PROGRESSES...WHICH SHOULD END THE DRIZZLE...BUT LOW CLOUDS
WILL REMAIN. SOME PATCHY FOG IS ANTICIPATED AND THIS COULD BECOME
DENSE ON THE RIDGES THROUGH STRATUS BUILD DOWN. THIS THREAT WILL
CONTINUE TO BE MONITORED. LOW CLOUDS HAVE CLEARED ACROSS PARTS OF
WESTERN IL...FAR WESTERN KY AND TN...BUT IT WILL PROBABLY BE AFTER
SUNRISE BEFORE THE LOW CLOUDS BEGIN TO LIFT ACROSS EASTERN KY.
MODEL TIME HEIGHT SECTIONS AND FORECAST SOUNDINGS SUGGEST THE LOW
CLOUDS LINGERING PAST 8 AM ON SATURDAY IN MANY LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 310 PM EDT FRI MAR 20 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF
KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA.
THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME
POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW
CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE
RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID
TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN
THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A
DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A
SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON
WEST TO NORTHWEST WINDS OF 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS
EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE
NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL
HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN
BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A
BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY
AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE
ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO
SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY
MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER
RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT
TERM.
SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH
BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG
AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE
FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP.
IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN
ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED
THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE
NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS
WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND
PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA
SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN
LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL
RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY
NIGHT...DESPITE THE HIGH CLOUDS.
USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS
WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS
WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z
TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM EDT FRI MAR 20 2015
THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN
PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT
THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE
END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST
TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE
WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A
WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL
WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND.
IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY
TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST
U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM
SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN
IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH
AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A
STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE
OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A
COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE
GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION
CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS
TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN.
HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT
THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 125 AM EDT SAT MAR 21 2015
LOW CLOUDS AND DRIZZLE STILL HANGING IN AT MANY SITES TONIGHT.
AREAS OF DRIZZLE ARE EXPECTED TO CONTINUE TO SUBSIDE OVERNIGHT AS
DRIER AIR SLOWLY WORKS EAST. MOST SITES WILL STAY IFR OR MVFR
THROUGH MID MORNING AT THE LATEST BEFORE WE BEGIN TO SEE SKIES
SCATTER OUT FROM WEST TO EAST. VFR CONDITIONS RETURN FOR MUCH OF
THE END OF THE TAF PERIOD AS DRYER AIR CONTINUES TO WORK EAST.
LIGHT WEST WINDS WILL GENERALLY PREVAIL THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1112 PM CDT FRI MAR 20 2015
.UPDATE...
ISSUED AT 1112 PM CDT FRI MAR 20 2015
AVIATION UPDATE.
UPDATE ISSUED AT 940 PM CDT FRI MAR 20 2015
UPDATED FORECAST TO INCREASE SKY COVER THROUGH THE REMAINDER OF THE
NIGHT. AS LOW CLOUDS CONTINUE TO CLEAR...HIGH CLOUDS ARE ON THE
INCREASE. MODEL FORECAST OF 300 MB DEWPOINT DEPRESSION SUGGESTS THIS
HIGH CLOUD COVER WILL LIKELY STICK AROUND THROUGH MUCH OF THE NIGHT.
REMAINDER OF FORECAST IS UNCHANGED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 1249 PM CDT FRI MAR 20 2015
LOW LEVEL TRAJECTORIES NOT FAVORABLE FOR RAPID CLEAR OUT...BUT
SLOWLY OVER TIME...HIGH PRESSURE WORKS IN AND ACROSS THE TENNESSEE
VALLEY AND OVERALL SUBSIDENCE/DRYING THROUGH THE COLUMN SHOULD WIN
OUT...CERTAINLY...BY TMRW. THIS WILL RESULT IN A NICE WARMUP WITH
TEMPS CLIMBING THRU THE 60S AND FLIRTING WITH/REACHING TOWARD 70
ESP ACROSS OUR SOUTH/WEST.
A MORE OR LESS ZONAL FLOW THEN RIDES OUT THE REMAINDER OF THE
SHORT TERM AND CARRIES THE FORECAST THRU THE WEEKEND. ENERGY IN
THE FLOW PATTERN TO OUR NORTH AND SOUTH MEANS MORE CLOUDS SUNDAY
THAN SATURDAY...AND AS A RESULT...TEMPS MAY NOT CLIMB AS HIGH BUT
WILL STILL BE RELATIVELY PLEASANT IN THE 60S.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 1249 PM CDT FRI MAR 20 2015
HIGH CONFIDENCE THROUGH MID WEEK....DECREASING TO LOW CONFIDENCE
AFTER THURSDAY.
THE MODELS ARE IN GOOD AGREEMENT WITH NEXT SYSTEM TO MOVE THROUGH
MID WEEK...BUT AFTER THAT THEY DIVERGE A GREAT DEAL. THEY BOTH KEEP
US UNDER A SLOW MOVING UPPER TROUGH BUT DIFFER IN SPOKES OF ENERGY
MOVING THROUGH THE TROF AND AVAILABLE MOISTURE. THE GFS CONTINUES TO
SHOW NUMEROUS SPOKES OF ENERGY PRODUCING LIGHT RAIN AFTER THE MAIN
COLD FRONT PASSAGE IN CONTRAST TO SEVERAL RUNS OF THE ECMWF WHICH
KEEPS US DRY AFTER THURSDAY. MAY HAVE SOME SLIGHT CHANCES IN FOR THE
POSSIBILITY THE GFS VERIFIES BUT WILL WAIT AND SEE WHAT THE EXTENDED
INIT YIELDS AND TAKE IT FROM THERE. I INTRODUCED THUNDER YESTERDAY
AND NOW THINK IT WILL BE SURFACE BASED WITH LI`S AT THE SURFACE
YIELDING -1 TO -4. ALSO K INDEX 30 AND ABOVE WITH SHOWALTER ZERO
TO -4. WILL KEEP TRW- OVER THE ENTIRE AREA THROUGH 00Z THURSDAY
AND THEN TAPER IT OFF TO ALONG AND SOUTHEAST OF THE OHIO RIVER
0-06Z THU. PLAN ON TAKING THUNDER COMPLETELY OUT AFTER 06Z
THURSDAY. THE THUNDER WILL BE POSSIBLE IN THE WARM SECTOR AFTER
THE WARM FRONT HAS LIFTED NORTH AND AHEAD OF THE APPROACHING COLD
FRONT FROM THE NORTHWEST.
SLIGHTLY ABOVE NORMAL TEMPERATURES FOR MOST OF THE WORK WEEK WILL
FALL BELOW NORMAL IN THE COLD FRONTS WAKE AT THE END OF THE WORK
WEEK.
&&
.AVIATION...
ISSUED AT 1112 PM CDT FRI MAR 20 2015
CONSIDERABLE HIGH CLOUDS OVERNIGHT. WINDS NOT ENTIRELY CALM
THROUGH 06Z. GUIDANCE SUGGESTS CALM BUT THE RAP 13KM SAYS IT MAY
NOT STAY THAT WAY (2-3 KTS AT TIMES). GIVEN BOTH FACTORS...WILL
LIMIT THE FOG MENTION. HIGH CLOUDS WILL PERSIST THROUGH SATURDAY
AS WELL WITH LIGHT WINDS CONTINUING...MAINLY WITH A SSW COMPONENT.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1027 AM EDT SAT MAR 21 2015
OVERALL...JUST MINOR TWEAKS TO THE GOING FORECAST...LARGELY TO THE
LAKE EFFECT POPS/CLOUDS TO MATCH UP WITH THE ONGOING SNOW SHOWERS.
WITH RAP ANALYZED 850MB TEMPS AROUND -16C OVER LAKE
SUPERIOR...THERE IS PLENTY OF OVER THE LAKE INSTABILITY TO LEAD TO
LAKE EFFECT. BUT THE COMBINATION OF THE REMAINING ICE AND LIMITED
MOISTURE HAS IMPACTED THE COVERAGE SO FAR THIS MORNING UNDER
GENERALLY NORTHERLY WINDS. THUS...AREAS OVER THE KEWEENAW PENINSULA
AND TOWARDS LUCE COUNTY HAVE BEEN MOSTLY SUNNY DUE TO THE UPSTREAM
ICE COVER. HAVE TRIMMED BACK POPS/CLOUDS FOR THOSE AREAS THROUGH
THE MORNING AND EARLY AFTERNOON UNTIL 950-925MB WINDS BEGIN TO BACK
TOWARDS 290-300 DEGREES AROUND 18Z. THEN TRENDED POPS UP DOWNSTREAM
OF THE ICE FREE AREAS OF LAKE SUPERIOR WITH THAT WIND DIRECTION.
OTHERWISE...TRENDED POPS UP TO HIGH CHANCE VALUES FOR THE NORTH
CENTRAL THIS MORNING WITH THE OPEN WATER SOUTHEAST OF THE KEWEENAW
PENINSULA AND FAVORED WIND DIRECTION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT SAT MAR 21 2015
SPRING IN UPPER MI USUALLY MEANS MORE SNOW...SO HERE WE GO. THE CWA
IS CURRENTLY IN BETWEEN WEATHER MAKERS. THE INITIAL LOW AND
ASSOCIATED COLD FRONT THAT BROUGH A MIXED BAG OF PRECIP ARE EXITING
FAR E UPPER MI/LAKE HURON. THE SECOND WEATHER MAKER IS IN THE FORM
OF COOLER AIR THAT WILL BE PUSHING IN ON FAVORABLE N-NW WINDS LATER
THIS MORNING. HOWEVER...A CLEARING SKY HAS BEEN THE RESULT OVER MUCH
OF THE W HALF OF UPPER MI AS DRY AIR LOOKS TO BE STEADY FORCE
UPSTREAM. THIS HAS BEEN MORE TEMPORARY OVER THE KEWEENAW AS LAKE
EFFECT CLOUDS DEVELOP IN THE OPEN WATERS TO THE N. ICE
COVER...ALTHOUGH THIN...LOOKS EXPANSIVE N OF SLEEPING AND MISERY
BAYS /NE OF ONTONAGON/. THIS WILL INHIBIT SOME OF THE LES THAT IS
EXPECTED TO DEVELOP LATER TODAY AS 850MB TEMPS FALL FROM AN AVERAGE -
10C EARLY THIS MORNING TO -13C BY THE END OF THE DAY...AND -16C BY
06Z SUNDAY. NOT EXPECTING MUCH SNOW...WHICH WILL BE ALONG THE
TRADITIONAL N-NW LES AREAS. WITH THE COOLER AIR SWEEPING IN..EXPECT
HIGHS ONLY IN THE 20S OR 30S. NORMAL HIGHS THIS TIME OF YEAR ARE IN
THE MID TO UPPER 30S. THE SFC HIGH OVER MUCH OF CENTRAL CANADA WILL
CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES...WITH THE N FLOW
CONTINUING...BUT LIGHTER. THIS WILL KEEP WINDS AROUND 5KTS THROUGH
THE OVERNIGHT HOURS. LOWERED THE FCST SLIGHTLY FOR TONIGHT...WITH
THE COLDEST AIR SLOWLY EXITING TO THE E...AND LIGHT WINDS AS THE SFC
HIGH SHIFTS MORE OVERHEAD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 536 AM EDT SAT MAR 21 2015
THRU LATE MONTH AND INTO EARLY APR...IT APPEARS PATTERN WILL
CONTINUE TO FAVOR RIDGING OVER WRN NAMERICA AND TROFFING OVER ERN
NAMERICA. AS A RESULT...WHILE THERE WILL BE OCCASIONAL DAYS OF ABOVE
NORMAL TEMPS FOR UPPER MI...THE PATTERN ON THE WHOLE WILL SUPPORT
NORMAL TO BELOW NORMAL TEMPS WITH BLO NORMAL LIKELY THE MORE COMMON
OUTCOME FOR THE MAJORITY OF DAYS. THE MJO IS CURRENTLY VERY
STRONG...AND WHILE IT IS FCST TO WEAKEN...THE PHASE OF THE MJO WILL
FAVOR BLO NORMAL TEMPS FOR THE GREAT LAKES LATE THIS MONTH INTO
EARLY APR...FURTHER SUPPORTING THE COOL INDICATIONS FROM OTHER
GUIDANCE. WITH NW FLOW MOSTLY PREVAILING...PCPN OVERALL WILL ALSO
LIKELY BE BLO NORMAL FOR AT LEAST THE NEXT 2-3 WEEKS...CONTINUING
THE DRY SYNOPTIC TREND NOTED FOR THE YEAR SO FAR (NEARLY ALL OF
UPPER MI IS RUNNING BLO NORMAL PCPN FOR THE YEAR...AND MUCH OF WI
INTO PORTIONS OF SCNTRL AND WRN UPPER MI ARE JUST 25-50PCT OF NORMAL
PCPN). WHILE BLO NORMAL PCPN WILL BE FAVORED OVERALL...THERE WILL BE
ONE SYSTEM AT THE MIDDLE OF NEXT WEEK THAT SHOULD PROVIDE WIDESPREAD
MDT PCPN...A RARE EVENT FOR UPPER MI SO FAR THIS YEAR. MORE ON THAT
LATER.
BEGINNING SUN...WITH 850MB TEMPS AS LOW AS -20C OVER ERN LAKE
SUPERIOR...EXPECT NW FLOW LES INTO AREAS EAST OF MARQUETTE. THE
LARGER OPEN WATER AREA TO THE LEE OF THE KEWEENAW WILL BE A PLUS FOR
LES INTO ALGER COUNTY. ALTHOUGH FCST SOUNDINGS SHOW INVERSIONS AT
AROUND 4KFT...THE DGZ OCCUPIES MUCH OF THE CONVECTIVE LAYER...AND
THAT MAY HELP FLUFF UP AN INCH OR 2 OF SNOW ACCUMULATION IF SHSN ARE
PERSISTENT AT ANY ONE LOCATION SUN MORNING. WITH MUCH MORE
PRONOUNCED ANTICYCLONIC FLOW INTO WRN LAKE SUPERIOR ASSOCIATED WITH
SFC HIGH PRES RIDGE NOSING INTO THE UPPER LAKES AND WITH 850MB TEMPS
ONLY AROUND -13C AT 12Z SUN...THERE MAY NOT BE MUCH MORE THAN
FLURRIES OFF WRN LAKE SUPERIOR DESPITE CONSIDERABLY MORE OPEN WATER
THAN OVER ERN LAKE SUPERIOR. MODERATION OF 850MB TEMPS SUN AFTN
WORKING IN CONCERT WITH THE DISRUPTIVE EFFECT OF SPRINGTIME SOLAR
INSOLATION ON LES WILL LIKELY SPELL AN END TO LES IN THE AFTN OVER
THE E OR AT LEAST A DIMINISHING TO FLURRIES. EXPECT HIGHS IN THE 20S
AND 30S...WARMEST TOWARD THE MI/WI BORDER.
SUN NIGHT/MON LOOK QUIET WITH SFC HIGH PRES IN CONTROL. AS WAS THE
CASE YESTERDAY...MODELS SHOWS A SHORTWAVE MOVING FROM THE DAKOTAS
INTO THE WRN GREAT LAKES WITH ASSOCIATED PCPN SPREADING ACROSS MN/WI
SUN NIGHT. GEM AND ECMWF BRING PCPN VERY NEAR THE WI/MI BORDER.
GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES AND DRY AIR EMANATING
FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF
HERE...A DRY FCST IS THE WAY TO GO. SUN NIGHT SHOULD BE QUITE
CHILLY...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH CLOUDS WILL BE
THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT
TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO.
MON NIGHT/TUE...ANOTHER WEAKENING SHORTWAVE WILL TRACK ESE INTO THE
WRN LAKES MON NIGHT. AT THE SAME TIME...UPPER RIDGE WILL BE MOVING
INTO THE UPPER MISSISSIPPI VALLEY/WRN GREAT LAKES DOWNSTREAM OF
FALLING HEIGHTS/STRONGER WAVE SHIFTING ACROSS THE NRN ROCKIES INTO
THE NRN PLAINS. THIS WILL SUPPORT LARGE SFC HIGH PRES OVER THE GREAT
LAKES REGION MON NIGHT THAT WILL DRIFT TOWARD NEW ENGLAND TUE. AS A
RESULT...ANY PCPN ASSOCIATED WITH WEAKENING SHORTWAVE SHOULD
DISSIPATE WITH TIME BEFORE REACHING UPPER MI.
NOW ONTO THE MAIN FEATURE FOR THIS FCST PERIOD. COMPLEX OF SHORTWAVE
ENERGY MOVING ONSHORE OVER THE PACIFIC NW SUN NIGHT/MON MORNING
WILL REACH THE WRN PLAINS TUE AND THEN MOVE ACROSS THE WRN GREAT
LAKES WED. 00Z MODEL GUIDANCE HAS OVERALL TRENDED MORE ROBUST WITH
THE MAIN SHORTWAVE ENERGY REACHING NEBRASKA TUE AND THEN WI/MI WED
MORNING. COMPLICATING FACTOR IS ADDITIONAL SHORTWAVE ENERGY MOVING
MORE SLOWLY ACROSS THE DAKOTAS AND HOW IT AFFECTS/INTERACTS WITH THE
MAIN WAVE. THIS WILL NO DOUBT CAUSE FLUCTUATIONS IN THE UPCOMING
MODEL RUNS...AND IT PROBABLY WON`T BE CLARIFIED UNTIL WE GET INTO
THE SHORT RANGE WITH THIS SYSTEM. THAT SAID...AS MENTIONED...MODELS
FOR NOW HAVE OVERALL TRENDED STRONGER WITH THE MAIN WAVE WHICH TAKES
ON A BRIEF NEGATIVE TILT AT AN OPTIMUM TIME AS IT SWINGS INTO THE
WRN GREAT LAKES. LOOKS LIKE QUITE THE DYNAMIC SYSTEM WITH 00Z
GFS/ECMWF SHOWING CENTER OF IMPRESSIVE 12HR 500MB HEIGHT FALLS OF
170-200M TRACKING ACROSS WI INTO ERN UPPER MI/STRAITS AREA. ALSO
NOTED IS STRONG DIFFLUENCE IN LEFT EXIT OF 100+KT UPPER JET AIMING
INTO LWR MI. ISENTROPIC ANALYSIS SHOWS MIXING RATIOS OF 3 TO 3.5G/KG
AVBL AROUND 750MB. WITH WHAT LOOKS LIKE ABOUT 9HRS OF GOOD ASCENT...
THIS WOULD SUGGEST THE POTENTIAL FOR ROUGHLY 5 INCHES OF SNOW. GIVEN
THE STRONG DYNAMICS...THAT WILL PROBABLY BE A CONSERVATIVE NUMBER
FOR THE MAX POTENTIAL SNOW ACCUMULATIONS. FOR QPF FROM THE MODELS...
THE STRONGER TREND HAS RESULTED IN AN UPTICK IN PCPN AMOUNTS WITH
THE 00Z ECMWF NOW COMING IN WITH A SOLID ONE-HALF TO TWO-THIRDS OF
AN INCH OF PCPN ACROSS THE FCST AREA. THE GFS HAS A LARGER SPREAD
FROM ABOUT 0.2 OVER THE KEWEENAW TO AROUND 0.75 INCHES NEAR LAKE MI.
THE GEM HAS CONSIDERABLY LESS PCPN ACROSS UPPER MI AS IT PASSES THE
MAIN SHORTWAVE/PCPN AREA SE OF UPPER MI. PTYPE WILL BE AN ISSUE AS
THERMAL PROFILES FROM CURRENT AND PREVIOUS MODEL RUNS SUGGEST THERE
WILL PROBABLY BE RAIN OR RAIN/SNOW MIX FOR A TIME AT MOST
LOCATIONS...AT LEAST AT THE ONSET OF PCPN. STRONG DYNAMIC
FORCING/HEIGHT FALLS SHOULD MAKE THE PERIOD OF LIQUID PCPN SHORT-
LIVED...ESPECIALLY AT HIGHER ELEVATIONS. SO...WE`RE PROBABLY STILL
LOOKING AT MOSTLY SNOW FOR THIS SYSTEM...OCCURRING OVERNIGHT TUE
NIGHT INTO WED MORNING. AT THIS POINT...IT APPEARS TO BE A SOLID
ADVY EVENT...THOUGH HVY/WET SNOW (LOWER SNOW TO WATER RATIOS) COULD
MAKE THIS A WARNING EVENT FOR SOME PARTS OF THE FCST AREA IF CURRENT
FCST THINKING PANS OUT.
SNOW WILL DIMINISH FROM W TO E WED...AND SOME -SN MAY CONTINUE TO
LINGER INTO WED NIGHT WITH MID/UPPER TROF OVERHEAD. INFLUX OF COLDER
ON THU LOOKS SUFFICIENT FOR THE POTENTIAL OF LIGHT LES THAT MAY
LINGER INTO FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 142 PM EDT SAT MAR 21 2015
COLD AIR ALOFT MOVING OVER THE ICE FREE AREAS OF LAKE SUPERIOR HAS
LED TO LAKE EFFECT SNOW SHOWERS OVER PORTIONS OF UPPER MICHIGAN
THIS AFTERNOON ALONG WITH OCCASIONAL MVFR CEILINGS. EXPECT ANY
MVFR CEILINGS AT THE START OF THE PERIOD TO RISE TO VFR WITHIN A
COUPLE HOURS AS DRIER AIR MOVES INTO THE AREA. THESE VFR CONDITIONS
WILL PREVAIL AT THE TAF SITES INTO THE EVENING HOURS BEFORE ANOTHER
WEAK SURGE OF MOISTURE INCREASES THE LAKE EFFECT CLOUD COVERAGE
LATE THIS EVENING AND INTO THE OVERNIGHT HOURS AS WINDS TURN BACK
TO THE NORTH-NORTHWEST. THINK KSAW HAS THE BEST OPPORTUNITY FOR
HIGH END MVFR CEILINGS...SO HAVE INCLUDED IT IN THE FORECAST.
CONFIDENCE IS TOO LOW AT THE OTHER TWO SITES TO INCLUDE. THIS
MOISTURE WILL DEPART SUNDAY MORNING AND WINDS WILL BACK (LEADING TO
DIMINISHING CLOUDS/SNOW)...AS THE RIDGE CONTINUES TO MOVE OVER THE
REGION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT SAT MAR 21 2015
LOW PRESSURE OVER FAR S ONTARIO WILL CONTINUE TO EXIT E
TODAY...MAKING WAY FOR THE LARGE HIGH OVER MUCH OF CENTRAL CANADA TO
SLOWLY BUILD ACROSS THE UPPER GREAT LAKES. LOOK FOR THE WEAK RIDGE
ACROSS LAKE SUPERIOR TO BUILD SUNDAY INTO MONDAY. N-NNW GUSTS
NEARING 25-30KTS WILL BE POSSIBLE TODAY. THE HIGH WILL THEN SLIDE
ACROSS THE LOWER GREAT LAKES MONDAY NIGHT INTO TUESDAY. A LOW
PRESSURE OVER THE DAKOTAS ON TUESDAY WILL CROSS THE UPPER GREAT
LAKES LATE TUESDAY NIGHT INTO WEDNESDAY...AND EXIT INTO SE CANADA
WEDNESDAY NIGHT. ANOTHER ROUND OF GUSTS NEAR 25KTS WILL AGAIN BE
POSSIBLE LATE TUESDAY NIGHT THROUGH THRUSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...KF
LONG TERM...ROLFSON
AVIATION...SRF
MARINE...KF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1254 PM EDT SAT MAR 21 2015
.AVIATION...
AREAS OF DRIZZLE HAVE DEVELOPED IN ADVANCE OF THE PRIMARY
WINDSHIFT/COLD FRONT THAT IS SETTLING SOUTHWARD ACROSS
SOUTHEASTERN MICHIGAN. ORIENTATION OF THE BOUNDARY IN COMPARISON
TO THE MEAN FLOW BRINGS UNCERTAINTY TO THE EVENTUAL TIMING AND
SOUTHWARD PROGRESSION OF THE BOUNDARY DURING THE AFTERNOON HOURS.
WHILE LOW LEVEL MOISTURE WILL SCOUR OUT RAPIDLY ONCE THE WIND
SHIFT PUSHES THROUGH...SUSPECT THE DRIZZLE AND LOW CLOUD IN
ADVANCE OF THE BOUNDARY TO PERSIST A BIT LONGER ACROSS THE SOUTH
THAN WHAT IT APPEARS AT THE MOMENT. INTRODUCED A TEMPO GROUPING
FOR DRIZZLE FOR THE SOUTHERN TAF SITES.
FOR DTW...POTENTIAL EXISTS THIS AFTERNOON FOR A PERIOD OF IFR
CONDITIONS BOTH IN CIGS/VSBY RESTRICTIONS DUE TO POOLING OF
MOISTURE AHEAD OF A COLD FRONT BOUNDARY. INCLUDED A TEMPO GROUP
WITH SOME POSSIBLE DRIZZLE. GUSTY NORTHWEST WINDS ARE EXPECTED TO
INCREASE SUBSTANTIALLY AS DRIER AIR ADVECTS INTO FAR SOUTHEASTERN
MICHIGAN LATE THIS AFTERNOON.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILING BELOW 5000 FT UNTIL LATE AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 301 AM EDT SAT MAR 21 2015
SHORT TERM...TODAY AND TONIGHT
COOL PATTERN IS SETTING UP ONCE AGAIN AS A SUB 500 DAM 500MB LOW IS
DROPPING SOUTHWARD FROM HUDSON BAY. A JET STREAK WILL GIVE IT AN
EASTWARD NUDGE KEEPING IT OVER THE ONTARIO/QUEBEC BORDER TODAY BUT
WITH RIDGING DEVELOPING OVER THE WEST COAST...COOL NORTH FLOW WILL
PREVAIL ONCE AGAIN AS IT DID FOR MOST OF THE WINTER.
WE START THE WEEKEND OUT WITH A TROUGH OF LOW PRESSURE DIRECTLY
OVERHEAD AS IT TRACKS SOUTH AND EAST. A WEAK SFC LOW TRACKING
THROUGH THE TROUGH WILL LIFT NE INTO ONTARIO THIS MORNING AS
PRESSURE FALLS RELOCATE. THE SFC COLD FRONT WILL PASS THROUGH SE MI
FROM ABOUT 13-16Z WITH LITTLE FANFARE IN THE WAY OF PRECIP AS THERE
IS LITTLE FORCING OVER MOST OF THE AREA. THE RUC DOES SEEM TO HAVE A
DECENT HANDLE ON THE COVERAGE OF THE RAIN CURRENTLY FALLING ACROSS
THE STATE AND IT SUGGESTS THAT THE LINE OF SHOWERS COMING ON SHORE
NEAR MUSKEGON AS OF 06Z MAY CLIP THE NORTHERN COUNTIES AS IT
TRAVERSES SE MI ON ITS WAY E/NE TO ONTARIO. WILL CONTINUE THE CHANCE
POPS THROUGH THE MORNING ACROSS THE NORTH TO COVERAGE THE SCATTERED
SHOWERS.
AFTER THE COLD FRONT PASSES TO THE SOUTH...GUSTY NORTHERLY WINDS
WILL BEGIN FOR THE AFTERNOON HOURS. LOOK FOR GUSTS TO PEAK IN THE 20-
25 KNOT RANGE. THESE GUSTY WINDS WILL HELP USHER IN COLD AIR FROM
CANADA AS A LARGE AREA OF HIGH PRESSURE BEGINS BUILDING INTO THE
REGION. THE FRONTAL POSITION AND TIMING WILL PRODUCE A THERMAL
GRADIENT ACROSS THE CWA IN TERMS OF HIGH TEMPS AS SOUTHERN LOCATIONS
WILL KEEP SW FLOW AND WAA ADVECTION INTO THE EARLY AFTERNOON BEFORE
THE FRONT SHUTS IT DOWN. HIGHS COULD REACH 50 NEAR THE OHIO BORDER
WITH THE THUMB POSSIBLY FAILING TO REACH 40. BY SUNDAY MORNING...925
TEMPS WILL HAVE FALLEN TO THE NEGATIVE TEENS. THIS WILL MAKE FOR A
CHILLY NIGHT...SOME 10 TO 15 DEGREES BELOW NORMAL...WHICH IS 30F.
LONG TERM...SUNDAY THROUGH FRIDAY
MID LEVEL CONFLUENT FLOW WILL OVERSPREAD LOWER MI ON SUNDAY AS THE
POLAR LOW DEPARTS INTO THE CANADIAN MARITIMES. THIS WILL FORCE
SURFACE HIGH PRESSURE TO EXPAND FROM CENTRAL CANADA INTO THE ERN
GREAT LAKES BY MONDAY. ALTHOUGH THE CORE OF ARCTIC AIR WILL SLIDE
EAST OF THE REGION ON SUNDAY...850MB TEMPS WILL STILL HOLD STEADY IN
THE NEGATIVE TEENS OVER SE MI. POTENTIAL MIXING HEIGHTS FOR LATE
MARCH SUGGEST LEANING ON THE HIGH END OF MODEL GUIDANCE...WHICH
STILL INDICATES HIGH TEMPS ONLY IN THE 30S TO AROUND 40. THE SFC
HIGH WILL RESIDE OVER THE ERN GREAT LAKES MONDAY INTO TUESDAY...
SUSTAINING A LIGHT EASTERLY WIND COMPONENT TO SE MI. THE LINGERING
SHALLOW COLD AIRMASS COMBINED WITH THE FLOW OFF THE GREAT LAKES WILL
SUPPRESS TEMPS...KEEPING READINGS ROUGHLY 10 DEGREES BELOW SEASONAL
NORMS FOR THE START OF THE WORK WEEK. THE 00Z MODEL SUITE CONTINUE
TO SHOW A REGION OF ENHANCED ISENTROPIC ASCENT SLIDING ACROSS THE
UPPER MS VALLEY SUN INTO SUN NIGHT...WHICH WILL RESULT IN SOME
MID/HIGH CLOUDS PASSING ACROSS SRN MI. THE DRY AIR ASSOCIATED WITH
THE SFC HIGH WILL KEEP THE FORECAST AREA PRECIP FREE.
THE NEXT CHANCE FOR PRECIP IS STILL EXPECTED TUES NIGHT INTO
WEDNESDAY. AMPLIFICATION OF A FAST MOVING MID LEVEL WAVE IN THE LEE
OF THE ROCKIES TUESDAY IS SHOWN BY THE 00Z MODEL SUITE. A NARROW
RIBBON OF ENHANCED MOISTURE TRANSPORT IS EXPECTED TO FUNNEL INTO
LOWER MI IN ADVANCE OF THIS WAVE AS IT LIFTS INTO THE GREAT LAKES
REGION TUES NIGHT. THE 00Z GFS BECOMES CONSIDERABLY MORE AMPLIFIED
WITH THIS WAVE AND ITS ASSOCIATED SFC LOW BY WED MORNING IN
COMPARISON TO THE ECMWF AND CANADIAN. IN LIGHT OF THE FAST FLOW AND
FAIRLY MARGINAL UPPER JET SUPPORT...THE WEAKER SOLUTIONS ARE
PREFERRED. THIS STILL SUPPORTS A GOOD SHOT OF PRECIP ACROSS SE MI
WED NIGHT ASSOCIATED WITH THE MAIN SURGE OF DEEP LAYER MOISTURE. WET
BULB AFFECTS MAY ALLOW A BRIEF PERIOD OF SNOW TO OCCUR ON THE LEAD
EDGE OF THE PRECIP SHIELD. THE RATE OF LOW LEVEL WARMING IS HOWEVER
EXPECTED TO QUICKLY CHANGE PRECIP OVER TO ALL RAIN. THE EXPECTED
TRACK OF THE SURFACE LOW ACROSS THE NRN LAKES REGION WILL BRING SOME
MILD AIR INTO THE AREA ON WEDNESDAY. THIS WARMING LOOKS TO BE BRIEF
AS A TRANSITION TOWARD A MORE AMPLIFIED FLOW TAKES HOLD BY THE END
OF THE WEEK...FEATURING LONG WAVE TROUGH AMPLIFICATION ACROSS THE
ERN US. THIS SUGGESTS TEMPS FALLING BACK ON THE COOL SIDE OF LATE
MARCH NORMS BY THE END OF THE FORECAST PERIOD.
MARINE...
WINDS WILL VEER TO THE NORTHWEST EARLY THIS MORNING WITH THE PASSAGE
OF A COLD FRONT. ARCTIC AIR WILL THEN FUNNEL INTO THE REGION UNDER A
STRENGTHENING N-NW GRADIENT TODAY INTO TONIGHT. THE GRADIENT FLOW
AND A DEEPENING MIXING LAYER WITHIN THE COLD AIR WILL SUPPORT WIND
GUSTS UP TO 30 KNOTS AT TIMES. SURFACE HIGH PRESSURE WILL BEGIN TO
BUILD ACROSS LOWER MI ON SUNDAY. THIS WILL ACTUALLY SUSTAIN THE N-NW
GRADIENT OVER NRN LAKE HURON...SUGGESTING SOME GUSTY WINDS
PERSISTING OVER THE OPEN LAKE. THE HIGH PRESSURE WILL THEN EXPAND
INTO THE EASTERN GREAT LAKES BY MONDAY...ALLOWING WIND SPEEDS TO
DRAMATICALLY DECREASE.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....CB
SHORT TERM...DRK
LONG TERM....SC
MARINE.......SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1027 AM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1027 AM EDT SAT MAR 21 2015
OVERALL...JUST MINOR TWEAKS TO THE GOING FORECAST...LARGELY TO THE
LAKE EFFECT POPS/CLOUDS TO MATCH UP WITH THE ONGOING SNOW SHOWERS.
WITH RAP ANALYZED 850MB TEMPS AROUND -16C OVER LAKE
SUPERIOR...THERE IS PLENTY OF OVER THE LAKE INSTABILITY TO LEAD TO
LAKE EFFECT. BUT THE COMBINATION OF THE REMAINING ICE AND LIMITED
MOISTURE HAS IMPACTED THE COVERAGE SO FAR THIS MORNING UNDER
GENERALLY NORTHERLY WINDS. THUS...AREAS OVER THE KEWEENAW PENINSULA
AND TOWARDS LUCE COUNTY HAVE BEEN MOSTLY SUNNY DUE TO THE UPSTREAM
ICE COVER. HAVE TRIMMED BACK POPS/CLOUDS FOR THOSE AREAS THROUGH
THE MORNING AND EARLY AFTERNOON UNTIL 950-925MB WINDS BEGIN TO BACK
TOWARDS 290-300 DEGREES AROUND 18Z. THEN TRENDED POPS UP DOWNSTREAM
OF THE ICE FREE AREAS OF LAKE SUPERIOR WITH THAT WIND DIRECTION.
OTHERWISE...TRENDED POPS UP TO HIGH CHANCE VALUES FOR THE NORTH
CENTRAL THIS MORNING WITH THE OPEN WATER SOUTHEAST OF THE KEWEENAW
PENINSULA AND FAVORED WIND DIRECTION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT SAT MAR 21 2015
SPRING IN UPPER MI USUALLY MEANS MORE SNOW...SO HERE WE GO. THE CWA
IS CURRENTLY IN BETWEEN WEATHER MAKERS. THE INITIAL LOW AND
ASSOCIATED COLD FRONT THAT BROUGH A MIXED BAG OF PRECIP ARE EXITING
FAR E UPPER MI/LAKE HURON. THE SECOND WEATHER MAKER IS IN THE FORM
OF COOLER AIR THAT WILL BE PUSHING IN ON FAVORABLE N-NW WINDS LATER
THIS MORNING. HOWEVER...A CLEARING SKY HAS BEEN THE RESULT OVER MUCH
OF THE W HALF OF UPPER MI AS DRY AIR LOOKS TO BE STEADY FORCE
UPSTREAM. THIS HAS BEEN MORE TEMPORARY OVER THE KEWEENAW AS LAKE
EFFECT CLOUDS DEVELOP IN THE OPEN WATERS TO THE N. ICE
COVER...ALTHOUGH THIN...LOOKS EXPANSIVE N OF SLEEPING AND MISERY
BAYS /NE OF ONTONAGON/. THIS WILL INHIBIT SOME OF THE LES THAT IS
EXPECTED TO DEVELOP LATER TODAY AS 850MB TEMPS FALL FROM AN AVERAGE -
10C EARLY THIS MORNING TO -13C BY THE END OF THE DAY...AND -16C BY
06Z SUNDAY. NOT EXPECTING MUCH SNOW...WHICH WILL BE ALONG THE
TRADITIONAL N-NW LES AREAS. WITH THE COOLER AIR SWEEPING IN..EXPECT
HIGHS ONLY IN THE 20S OR 30S. NORMAL HIGHS THIS TIME OF YEAR ARE IN
THE MID TO UPPER 30S. THE SFC HIGH OVER MUCH OF CENTRAL CANADA WILL
CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES...WITH THE N FLOW
CONTINUING...BUT LIGHTER. THIS WILL KEEP WINDS AROUND 5KTS THROUGH
THE OVERNIGHT HOURS. LOWERED THE FCST SLIGHTLY FOR TONIGHT...WITH
THE COLDEST AIR SLOWLY EXITING TO THE E...AND LIGHT WINDS AS THE SFC
HIGH SHIFTS MORE OVERHEAD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 536 AM EDT SAT MAR 21 2015
THRU LATE MONTH AND INTO EARLY APR...IT APPEARS PATTERN WILL
CONTINUE TO FAVOR RIDGING OVER WRN NAMERICA AND TROFFING OVER ERN
NAMERICA. AS A RESULT...WHILE THERE WILL BE OCCASIONAL DAYS OF ABOVE
NORMAL TEMPS FOR UPPER MI...THE PATTERN ON THE WHOLE WILL SUPPORT
NORMAL TO BELOW NORMAL TEMPS WITH BLO NORMAL LIKELY THE MORE COMMON
OUTCOME FOR THE MAJORITY OF DAYS. THE MJO IS CURRENTLY VERY
STRONG...AND WHILE IT IS FCST TO WEAKEN...THE PHASE OF THE MJO WILL
FAVOR BLO NORMAL TEMPS FOR THE GREAT LAKES LATE THIS MONTH INTO
EARLY APR...FURTHER SUPPORTING THE COOL INDICATIONS FROM OTHER
GUIDANCE. WITH NW FLOW MOSTLY PREVAILING...PCPN OVERALL WILL ALSO
LIKELY BE BLO NORMAL FOR AT LEAST THE NEXT 2-3 WEEKS...CONTINUING
THE DRY SYNOPTIC TREND NOTED FOR THE YEAR SO FAR (NEARLY ALL OF
UPPER MI IS RUNNING BLO NORMAL PCPN FOR THE YEAR...AND MUCH OF WI
INTO PORTIONS OF SCNTRL AND WRN UPPER MI ARE JUST 25-50PCT OF NORMAL
PCPN). WHILE BLO NORMAL PCPN WILL BE FAVORED OVERALL...THERE WILL BE
ONE SYSTEM AT THE MIDDLE OF NEXT WEEK THAT SHOULD PROVIDE WIDESPREAD
MDT PCPN...A RARE EVENT FOR UPPER MI SO FAR THIS YEAR. MORE ON THAT
LATER.
BEGINNING SUN...WITH 850MB TEMPS AS LOW AS -20C OVER ERN LAKE
SUPERIOR...EXPECT NW FLOW LES INTO AREAS EAST OF MARQUETTE. THE
LARGER OPEN WATER AREA TO THE LEE OF THE KEWEENAW WILL BE A PLUS FOR
LES INTO ALGER COUNTY. ALTHOUGH FCST SOUNDINGS SHOW INVERSIONS AT
AROUND 4KFT...THE DGZ OCCUPIES MUCH OF THE CONVECTIVE LAYER...AND
THAT MAY HELP FLUFF UP AN INCH OR 2 OF SNOW ACCUMULATION IF SHSN ARE
PERSISTENT AT ANY ONE LOCATION SUN MORNING. WITH MUCH MORE
PRONOUNCED ANTICYCLONIC FLOW INTO WRN LAKE SUPERIOR ASSOCIATED WITH
SFC HIGH PRES RIDGE NOSING INTO THE UPPER LAKES AND WITH 850MB TEMPS
ONLY AROUND -13C AT 12Z SUN...THERE MAY NOT BE MUCH MORE THAN
FLURRIES OFF WRN LAKE SUPERIOR DESPITE CONSIDERABLY MORE OPEN WATER
THAN OVER ERN LAKE SUPERIOR. MODERATION OF 850MB TEMPS SUN AFTN
WORKING IN CONCERT WITH THE DISRUPTIVE EFFECT OF SPRINGTIME SOLAR
INSOLATION ON LES WILL LIKELY SPELL AN END TO LES IN THE AFTN OVER
THE E OR AT LEAST A DIMINISHING TO FLURRIES. EXPECT HIGHS IN THE 20S
AND 30S...WARMEST TOWARD THE MI/WI BORDER.
SUN NIGHT/MON LOOK QUIET WITH SFC HIGH PRES IN CONTROL. AS WAS THE
CASE YESTERDAY...MODELS SHOWS A SHORTWAVE MOVING FROM THE DAKOTAS
INTO THE WRN GREAT LAKES WITH ASSOCIATED PCPN SPREADING ACROSS MN/WI
SUN NIGHT. GEM AND ECMWF BRING PCPN VERY NEAR THE WI/MI BORDER.
GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES AND DRY AIR EMANATING
FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF
HERE...A DRY FCST IS THE WAY TO GO. SUN NIGHT SHOULD BE QUITE
CHILLY...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH CLOUDS WILL BE
THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT
TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO.
MON NIGHT/TUE...ANOTHER WEAKENING SHORTWAVE WILL TRACK ESE INTO THE
WRN LAKES MON NIGHT. AT THE SAME TIME...UPPER RIDGE WILL BE MOVING
INTO THE UPPER MISSISSIPPI VALLEY/WRN GREAT LAKES DOWNSTREAM OF
FALLING HEIGHTS/STRONGER WAVE SHIFTING ACROSS THE NRN ROCKIES INTO
THE NRN PLAINS. THIS WILL SUPPORT LARGE SFC HIGH PRES OVER THE GREAT
LAKES REGION MON NIGHT THAT WILL DRIFT TOWARD NEW ENGLAND TUE. AS A
RESULT...ANY PCPN ASSOCIATED WITH WEAKENING SHORTWAVE SHOULD
DISSIPATE WITH TIME BEFORE REACHING UPPER MI.
NOW ONTO THE MAIN FEATURE FOR THIS FCST PERIOD. COMPLEX OF SHORTWAVE
ENERGY MOVING ONSHORE OVER THE PACIFIC NW SUN NIGHT/MON MORNING
WILL REACH THE WRN PLAINS TUE AND THEN MOVE ACROSS THE WRN GREAT
LAKES WED. 00Z MODEL GUIDANCE HAS OVERALL TRENDED MORE ROBUST WITH
THE MAIN SHORTWAVE ENERGY REACHING NEBRASKA TUE AND THEN WI/MI WED
MORNING. COMPLICATING FACTOR IS ADDITIONAL SHORTWAVE ENERGY MOVING
MORE SLOWLY ACROSS THE DAKOTAS AND HOW IT AFFECTS/INTERACTS WITH THE
MAIN WAVE. THIS WILL NO DOUBT CAUSE FLUCTUATIONS IN THE UPCOMING
MODEL RUNS...AND IT PROBABLY WON`T BE CLARIFIED UNTIL WE GET INTO
THE SHORT RANGE WITH THIS SYSTEM. THAT SAID...AS MENTIONED...MODELS
FOR NOW HAVE OVERALL TRENDED STRONGER WITH THE MAIN WAVE WHICH TAKES
ON A BRIEF NEGATIVE TILT AT AN OPTIMUM TIME AS IT SWINGS INTO THE
WRN GREAT LAKES. LOOKS LIKE QUITE THE DYNAMIC SYSTEM WITH 00Z
GFS/ECMWF SHOWING CENTER OF IMPRESSIVE 12HR 500MB HEIGHT FALLS OF
170-200M TRACKING ACROSS WI INTO ERN UPPER MI/STRAITS AREA. ALSO
NOTED IS STRONG DIFFLUENCE IN LEFT EXIT OF 100+KT UPPER JET AIMING
INTO LWR MI. ISENTROPIC ANALYSIS SHOWS MIXING RATIOS OF 3 TO 3.5G/KG
AVBL AROUND 750MB. WITH WHAT LOOKS LIKE ABOUT 9HRS OF GOOD ASCENT...
THIS WOULD SUGGEST THE POTENTIAL FOR ROUGHLY 5 INCHES OF SNOW. GIVEN
THE STRONG DYNAMICS...THAT WILL PROBABLY BE A CONSERVATIVE NUMBER
FOR THE MAX POTENTIAL SNOW ACCUMULATIONS. FOR QPF FROM THE MODELS...
THE STRONGER TREND HAS RESULTED IN AN UPTICK IN PCPN AMOUNTS WITH
THE 00Z ECMWF NOW COMING IN WITH A SOLID ONE-HALF TO TWO-THIRDS OF
AN INCH OF PCPN ACROSS THE FCST AREA. THE GFS HAS A LARGER SPREAD
FROM ABOUT 0.2 OVER THE KEWEENAW TO AROUND 0.75 INCHES NEAR LAKE MI.
THE GEM HAS CONSIDERABLY LESS PCPN ACROSS UPPER MI AS IT PASSES THE
MAIN SHORTWAVE/PCPN AREA SE OF UPPER MI. PTYPE WILL BE AN ISSUE AS
THERMAL PROFILES FROM CURRENT AND PREVIOUS MODEL RUNS SUGGEST THERE
WILL PROBABLY BE RAIN OR RAIN/SNOW MIX FOR A TIME AT MOST
LOCATIONS...AT LEAST AT THE ONSET OF PCPN. STRONG DYNAMIC
FORCING/HEIGHT FALLS SHOULD MAKE THE PERIOD OF LIQUID PCPN SHORT-
LIVED...ESPECIALLY AT HIGHER ELEVATIONS. SO...WE`RE PROBABLY STILL
LOOKING AT MOSTLY SNOW FOR THIS SYSTEM...OCCURRING OVERNIGHT TUE
NIGHT INTO WED MORNING. AT THIS POINT...IT APPEARS TO BE A SOLID
ADVY EVENT...THOUGH HVY/WET SNOW (LOWER SNOW TO WATER RATIOS) COULD
MAKE THIS A WARNING EVENT FOR SOME PARTS OF THE FCST AREA IF CURRENT
FCST THINKING PANS OUT.
SNOW WILL DIMINISH FROM W TO E WED...AND SOME -SN MAY CONTINUE TO
LINGER INTO WED NIGHT WITH MID/UPPER TROF OVERHEAD. INFLUX OF COLDER
ON THU LOOKS SUFFICIENT FOR THE POTENTIAL OF LIGHT LES THAT MAY
LINGER INTO FRI.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY NIGHT)
ISSUED AT 452 AM EDT SAT MAR 21 2015
ADDITIONAL SNOW SHOWERS WILL BE POSSIBLE TODAY AT ALL 3 TAF
SITES...WITH THE BEST CHANCE BEING AT CMX. CMX WILL BE CLOSER TO THE
COLDER AIR AND HAVE MORE FAVORABLE WINDS OUT OF A W TO N DIRECTION.
STEADY WINDS AND SIGNIFICANT/DOMINANT BANDED LAKE EFFECT SNOW
SHOWERS ARE NOT EXPECTED...JUST A FEW NUISANCE SNOW SHOWERS. GUSTS
NEAR 20KTS /ONCE AGAIN STRONGEST AT CMX/ WILL DIMINISH DURING THE
AFTERNOON HOURS AS LIGHTER WINDS/HIGH PRESSURE NEAR FROM THE
NORTHWEST. VFR CEILINGS/VIS ARE EXPECTED FOR MOST OF THIS PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT SAT MAR 21 2015
LOW PRESSURE OVER FAR S ONTARIO WILL CONTINUE TO EXIT E
TODAY...MAKING WAY FOR THE LARGE HIGH OVER MUCH OF CENTRAL CANADA TO
SLOWLY BUILD ACROSS THE UPPER GREAT LAKES. LOOK FOR THE WEAK RIDGE
ACROSS LAKE SUPERIOR TO BUILD SUNDAY INTO MONDAY. N-NNW GUSTS
NEARING 25-30KTS WILL BE POSSIBLE TODAY. THE HIGH WILL THEN SLIDE
ACROSS THE LOWER GREAT LAKES MONDAY NIGHT INTO TUESDAY. A LOW
PRESSURE OVER THE DAKOTAS ON TUESDAY WILL CROSS THE UPPER GREAT
LAKES LATE TUESDAY NIGHT INTO WEDNESDAY...AND EXIT INTO SE CANADA
WEDNESDAY NIGHT. ANOTHER ROUND OF GUSTS NEAR 25KTS WILL AGAIN BE
POSSIBLE LATE TUESDAY NIGHT THROUGH THRUSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...KF
LONG TERM...ROLFSON
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
700 AM EDT SAT MAR 21 2015
.AVIATION...
THE AREA OF RAIN OVER MID MI HAS REORGANIZED FURTHER NORTH WHICH IS
LEADING TO A DRIER FORECAST FOR MBS AND FNT. A COLD FRONT WILL DROP
THROUGH THE AREA THIS MORNING BRINGING BEHIND IT GUSTY NORTHERLY
FLOW...GUSTING TO AROUND 20 KNOTS...AND DRIER AIR. THIS DRY AIR WILL
ERODE THE CURRENT IFR CLOUD FIELD SET UP ACROSS SE MI SOUTH OF
THE FRONT IN THE MOISTURE RICH SW FLOW. THE DIMINISHING TREND
WILL LAST THROUGH THE EVENING AND OVERNIGHT. SOME MVFR VSBY
RESTRICTIONS ARE PRESENT BUT WILL DISSIPATE THROUGH THE MORNING
HOURS.
FOR DTW...MVFR VSBYS ARE MOVING NORTH INTO THE STATE AS MOISTURE
POOLS UP AHEAD OF AN APPROACHING COLD FRONT. IN ADDITION...IFR CIGS
ARE FILLING IN ACROSS SOUTHERN MI HEADING TOWARD THE METRO AREA
AND MAY AFFECT THE TERMINAL UNTIL THE COLD FRONT MOVES THROUGH
THIS MORNING. DRIER AIR BEHIND THE FRONT WILL RESULT IN A CLEARING
TREND THIS AFTERNOON AND EVENING.
//DTW THRESHOLD PROBABILITIES...
* MODERATE FOR CEILING BELOW 5000 FT THROUGH EARLY THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 301 AM EDT SAT MAR 21 2015
SHORT TERM...TODAY AND TONIGHT
COOL PATTERN IS SETTING UP ONCE AGAIN AS A SUB 500 DAM 500MB LOW IS
DROPPING SOUTHWARD FROM HUDSON BAY. A JET STREAK WILL GIVE IT AN
EASTWARD NUDGE KEEPING IT OVER THE ONTARIO/QUEBEC BORDER TODAY BUT
WITH RIDGING DEVELOPING OVER THE WEST COAST...COOL NORTH FLOW WILL
PREVAIL ONCE AGAIN AS IT DID FOR MOST OF THE WINTER.
WE START THE WEEKEND OUT WITH A TROUGH OF LOW PRESSURE DIRECTLY
OVERHEAD AS IT TRACKS SOUTH AND EAST. A WEAK SFC LOW TRACKING
THROUGH THE TROUGH WILL LIFT NE INTO ONTARIO THIS MORNING AS
PRESSURE FALLS RELOCATE. THE SFC COLD FRONT WILL PASS THROUGH SE MI
FROM ABOUT 13-16Z WITH LITTLE FANFARE IN THE WAY OF PRECIP AS THERE
IS LITTLE FORCING OVER MOST OF THE AREA. THE RUC DOES SEEM TO HAVE A
DECENT HANDLE ON THE COVERAGE OF THE RAIN CURRENTLY FALLING ACROSS
THE STATE AND IT SUGGESTS THAT THE LINE OF SHOWERS COMING ON SHORE
NEAR MUSKEGON AS OF 06Z MAY CLIP THE NORTHERN COUNTIES AS IT
TRAVERSES SE MI ON ITS WAY E/NE TO ONTARIO. WILL CONTINUE THE CHANCE
POPS THROUGH THE MORNING ACROSS THE NORTH TO COVERAGE THE SCATTERED
SHOWERS.
AFTER THE COLD FRONT PASSES TO THE SOUTH...GUSTY NORTHERLY WINDS
WILL BEGIN FOR THE AFTERNOON HOURS. LOOK FOR GUSTS TO PEAK IN THE 20-
25 KNOT RANGE. THESE GUSTY WINDS WILL HELP USHER IN COLD AIR FROM
CANADA AS A LARGE AREA OF HIGH PRESSURE BEGINS BUILDING INTO THE
REGION. THE FRONTAL POSITION AND TIMING WILL PRODUCE A THERMAL
GRADIENT ACROSS THE CWA IN TERMS OF HIGH TEMPS AS SOUTHERN LOCATIONS
WILL KEEP SW FLOW AND WAA ADVECTION INTO THE EARLY AFTERNOON BEFORE
THE FRONT SHUTS IT DOWN. HIGHS COULD REACH 50 NEAR THE OHIO BORDER
WITH THE THUMB POSSIBLY FAILING TO REACH 40. BY SUNDAY MORNING...925
TEMPS WILL HAVE FALLEN TO THE NEGATIVE TEENS. THIS WILL MAKE FOR A
CHILLY NIGHT...SOME 10 TO 15 DEGREES BELOW NORMAL...WHICH IS 30F.
LONG TERM...SUNDAY THROUGH FRIDAY
MID LEVEL CONFLUENT FLOW WILL OVERSPREAD LOWER MI ON SUNDAY AS THE
POLAR LOW DEPARTS INTO THE CANADIAN MARITIMES. THIS WILL FORCE
SURFACE HIGH PRESSURE TO EXPAND FROM CENTRAL CANADA INTO THE ERN
GREAT LAKES BY MONDAY. ALTHOUGH THE CORE OF ARCTIC AIR WILL SLIDE
EAST OF THE REGION ON SUNDAY...850MB TEMPS WILL STILL HOLD STEADY IN
THE NEGATIVE TEENS OVER SE MI. POTENTIAL MIXING HEIGHTS FOR LATE
MARCH SUGGEST LEANING ON THE HIGH END OF MODEL GUIDANCE...WHICH
STILL INDICATES HIGH TEMPS ONLY IN THE 30S TO AROUND 40. THE SFC
HIGH WILL RESIDE OVER THE ERN GREAT LAKES MONDAY INTO TUESDAY...
SUSTAINING A LIGHT EASTERLY WIND COMPONENT TO SE MI. THE LINGERING
SHALLOW COLD AIRMASS COMBINED WITH THE FLOW OFF THE GREAT LAKES WILL
SUPPRESS TEMPS...KEEPING READINGS ROUGHLY 10 DEGREES BELOW SEASONAL
NORMS FOR THE START OF THE WORK WEEK. THE 00Z MODEL SUITE CONTINUE
TO SHOW A REGION OF ENHANCED ISENTROPIC ASCENT SLIDING ACROSS THE
UPPER MS VALLEY SUN INTO SUN NIGHT...WHICH WILL RESULT IN SOME
MID/HIGH CLOUDS PASSING ACROSS SRN MI. THE DRY AIR ASSOCIATED WITH
THE SFC HIGH WILL KEEP THE FORECAST AREA PRECIP FREE.
THE NEXT CHANCE FOR PRECIP IS STILL EXPECTED TUES NIGHT INTO
WEDNESDAY. AMPLIFICATION OF A FAST MOVING MID LEVEL WAVE IN THE LEE
OF THE ROCKIES TUESDAY IS SHOWN BY THE 00Z MODEL SUITE. A NARROW
RIBBON OF ENHANCED MOISTURE TRANSPORT IS EXPECTED TO FUNNEL INTO
LOWER MI IN ADVANCE OF THIS WAVE AS IT LIFTS INTO THE GREAT LAKES
REGION TUES NIGHT. THE 00Z GFS BECOMES CONSIDERABLY MORE AMPLIFIED
WITH THIS WAVE AND ITS ASSOCIATED SFC LOW BY WED MORNING IN
COMPARISON TO THE ECMWF AND CANADIAN. IN LIGHT OF THE FAST FLOW AND
FAIRLY MARGINAL UPPER JET SUPPORT...THE WEAKER SOLUTIONS ARE
PREFERRED. THIS STILL SUPPORTS A GOOD SHOT OF PRECIP ACROSS SE MI
WED NIGHT ASSOCIATED WITH THE MAIN SURGE OF DEEP LAYER MOISTURE. WET
BULB AFFECTS MAY ALLOW A BRIEF PERIOD OF SNOW TO OCCUR ON THE LEAD
EDGE OF THE PRECIP SHIELD. THE RATE OF LOW LEVEL WARMING IS HOWEVER
EXPECTED TO QUICKLY CHANGE PRECIP OVER TO ALL RAIN. THE EXPECTED
TRACK OF THE SURFACE LOW ACROSS THE NRN LAKES REGION WILL BRING SOME
MILD AIR INTO THE AREA ON WEDNESDAY. THIS WARMING LOOKS TO BE BRIEF
AS A TRANSITION TOWARD A MORE AMPLIFIED FLOW TAKES HOLD BY THE END
OF THE WEEK...FEATURING LONG WAVE TROUGH AMPLIFICATION ACROSS THE
ERN US. THIS SUGGESTS TEMPS FALLING BACK ON THE COOL SIDE OF LATE
MARCH NORMS BY THE END OF THE FORECAST PERIOD.
MARINE...
WINDS WILL VEER TO THE NORTHWEST EARLY THIS MORNING WITH THE PASSAGE
OF A COLD FRONT. ARCTIC AIR WILL THEN FUNNEL INTO THE REGION UNDER A
STRENGTHENING N-NW GRADIENT TODAY INTO TONIGHT. THE GRADIENT FLOW
AND A DEEPENING MIXING LAYER WITHIN THE COLD AIR WILL SUPPORT WIND
GUSTS UP TO 30 KNOTS AT TIMES. SURFACE HIGH PRESSURE WILL BEGIN TO
BUILD ACROSS LOWER MI ON SUNDAY. THIS WILL ACTUALLY SUSTAIN THE N-NW
GRADIENT OVER NRN LAKE HURON...SUGGESTING SOME GUSTY WINDS
PERSISTING OVER THE OPEN LAKE. THE HIGH PRESSURE WILL THEN EXPAND
INTO THE EASTERN GREAT LAKES BY MONDAY...ALLOWING WIND SPEEDS TO
DRAMATICALLY DECREASE.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....DRK
SHORT TERM...DRK
LONG TERM....SC
MARINE.......SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
301 AM EDT SAT MAR 21 2015
.SHORT TERM...TODAY AND TONIGHT
COOL PATTERN IS SETTING UP ONCE AGAIN AS A SUB 500 DAM 500MB LOW IS
DROPPING SOUTHWARD FROM HUDSON BAY. A JET STREAK WILL GIVE IT AN
EASTWARD NUDGE KEEPING IT OVER THE ONTARIO/QUEBEC BORDER TODAY BUT
WITH RIDGING DEVELOPING OVER THE WEST COAST...COOL NORTH FLOW WILL
PREVAIL ONCE AGAIN AS IT DID FOR MOST OF THE WINTER.
WE START THE WEEKEND OUT WITH A TROUGH OF LOW PRESSURE DIRECTLY
OVERHEAD AS IT TRACKS SOUTH AND EAST. A WEAK SFC LOW TRACKING
THROUGH THE TROUGH WILL LIFT NE INTO ONTARIO THIS MORNING AS
PRESSURE FALLS RELOCATE. THE SFC COLD FRONT WILL PASS THROUGH SE MI
FROM ABOUT 13-16Z WITH LITTLE FANFARE IN THE WAY OF PRECIP AS THERE
IS LITTLE FORCING OVER MOST OF THE AREA. THE RUC DOES SEEM TO HAVE A
DECENT HANDLE ON THE COVERAGE OF THE RAIN CURRENTLY FALLING ACROSS
THE STATE AND IT SUGGESTS THAT THE LINE OF SHOWERS COMING ON SHORE
NEAR MUSKEGON AS OF 06Z MAY CLIP THE NORTHERN COUNTIES AS IT
TRAVERSES SE MI ON ITS WAY E/NE TO ONTARIO. WILL CONTINUE THE CHANCE
POPS THROUGH THE MORNING ACROSS THE NORTH TO COVERAGE THE SCATTERED
SHOWERS.
AFTER THE COLD FRONT PASSES TO THE SOUTH...GUSTY NORTHERLY WINDS
WILL BEGIN FOR THE AFTERNOON HOURS. LOOK FOR GUSTS TO PEAK IN THE 20-
25 KNOT RANGE. THESE GUSTY WINDS WILL HELP USHER IN COLD AIR FROM
CANADA AS A LARGE AREA OF HIGH PRESSURE BEGINS BUILDING INTO THE
REGION. THE FRONTAL POSITION AND TIMING WILL PRODUCE A THERMAL
GRADIENT ACROSS THE CWA IN TERMS OF HIGH TEMPS AS SOUTHERN LOCATIONS
WILL KEEP SW FLOW AND WAA ADVECTION INTO THE EARLY AFTERNOON BEFORE
THE FRONT SHUTS IT DOWN. HIGHS COULD REACH 50 NEAR THE OHIO BORDER
WITH THE THUMB POSSIBLY FAILING TO REACH 40. BY SUNDAY MORNING...925
TEMPS WILL HAVE FALLEN TO THE NEGATIVE TEENS. THIS WILL MAKE FOR A
CHILLY NIGHT...SOME 10 TO 15 DEGREES BELOW NORMAL...WHICH IS 30F.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
MID LEVEL CONFLUENT FLOW WILL OVERSPREAD LOWER MI ON SUNDAY AS THE
POLAR LOW DEPARTS INTO THE CANADIAN MARITIMES. THIS WILL FORCE
SURFACE HIGH PRESSURE TO EXPAND FROM CENTRAL CANADA INTO THE ERN
GREAT LAKES BY MONDAY. ALTHOUGH THE CORE OF ARCTIC AIR WILL SLIDE
EAST OF THE REGION ON SUNDAY...850MB TEMPS WILL STILL HOLD STEADY IN
THE NEGATIVE TEENS OVER SE MI. POTENTIAL MIXING HEIGHTS FOR LATE
MARCH SUGGEST LEANING ON THE HIGH END OF MODEL GUIDANCE...WHICH
STILL INDICATES HIGH TEMPS ONLY IN THE 30S TO AROUND 40. THE SFC
HIGH WILL RESIDE OVER THE ERN GREAT LAKES MONDAY INTO TUESDAY...
SUSTAINING A LIGHT EASTERLY WIND COMPONENT TO SE MI. THE LINGERING
SHALLOW COLD AIRMASS COMBINED WITH THE FLOW OFF THE GREAT LAKES WILL
SUPPRESS TEMPS...KEEPING READINGS ROUGHLY 10 DEGREES BELOW SEASONAL
NORMS FOR THE START OF THE WORK WEEK. THE 00Z MODEL SUITE CONTINUE
TO SHOW A REGION OF ENHANCED ISENTROPIC ASCENT SLIDING ACROSS THE
UPPER MS VALLEY SUN INTO SUN NIGHT...WHICH WILL RESULT IN SOME
MID/HIGH CLOUDS PASSING ACROSS SRN MI. THE DRY AIR ASSOCIATED WITH
THE SFC HIGH WILL KEEP THE FORECAST AREA PRECIP FREE.
THE NEXT CHANCE FOR PRECIP IS STILL EXPECTED TUES NIGHT INTO
WEDNESDAY. AMPLIFICATION OF A FAST MOVING MID LEVEL WAVE IN THE LEE
OF THE ROCKIES TUESDAY IS SHOWN BY THE 00Z MODEL SUITE. A NARROW
RIBBON OF ENHANCED MOISTURE TRANSPORT IS EXPECTED TO FUNNEL INTO
LOWER MI IN ADVANCE OF THIS WAVE AS IT LIFTS INTO THE GREAT LAKES
REGION TUES NIGHT. THE 00Z GFS BECOMES CONSIDERABLY MORE AMPLIFIED
WITH THIS WAVE AND ITS ASSOCIATED SFC LOW BY WED MORNING IN
COMPARISON TO THE ECMWF AND CANADIAN. IN LIGHT OF THE FAST FLOW AND
FAIRLY MARGINAL UPPER JET SUPPORT...THE WEAKER SOLUTIONS ARE
PREFERRED. THIS STILL SUPPORTS A GOOD SHOT OF PRECIP ACROSS SE MI
WED NIGHT ASSOCIATED WITH THE MAIN SURGE OF DEEP LAYER MOISTURE. WET
BULB AFFECTS MAY ALLOW A BRIEF PERIOD OF SNOW TO OCCUR ON THE LEAD
EDGE OF THE PRECIP SHIELD. THE RATE OF LOW LEVEL WARMING IS HOWEVER
EXPECTED TO QUICKLY CHANGE PRECIP OVER TO ALL RAIN. THE EXPECTED
TRACK OF THE SURFACE LOW ACROSS THE NRN LAKES REGION WILL BRING SOME
MILD AIR INTO THE AREA ON WEDNESDAY. THIS WARMING LOOKS TO BE BRIEF
AS A TRANSITION TOWARD A MORE AMPLIFIED FLOW TAKES HOLD BY THE END
OF THE WEEK...FEATURING LONG WAVE TROUGH AMPLIFICATION ACROSS THE
ERN US. THIS SUGGESTS TEMPS FALLING BACK ON THE COOL SIDE OF LATE
MARCH NORMS BY THE END OF THE FORECAST PERIOD.
&&
.MARINE...
WINDS WILL VEER TO THE NORTHWEST EARLY THIS MORNING WITH THE PASSAGE
OF A COLD FRONT. ARCTIC AIR WILL THEN FUNNEL INTO THE REGION UNDER A
STRENGTHENING N-NW GRADIENT TODAY INTO TONIGHT. THE GRADIENT FLOW
AND A DEEPENING MIXING LAYER WITHIN THE COLD AIR WILL SUPPORT WIND
GUSTS UP TO 30 KNOTS AT TIMES. SURFACE HIGH PRESSURE WILL BEGIN TO
BUILD ACROSS LOWER MI ON SUNDAY. THIS WILL ACTUALLY SUSTAIN THE N-NW
GRADIENT OVER NRN LAKE HURON...SUGGESTING SOME GUSTY WINDS
PERSISTING OVER THE OPEN LAKE. THE HIGH PRESSURE WILL THEN EXPAND
INTO THE EASTERN GREAT LAKES BY MONDAY...ALLOWING WIND SPEEDS TO
DRAMATICALLY DECREASE.
&&
.AVIATION...ISSUED 121 AM EDT SAT MAR 21 2015
MVFR CEILING WILL CONVERGE ON THE SE MICHIGAN TERMINAL CORRIDOR
DURING THE EARLY MORNING FROM THE NORTH WITH A COLD FRONT AND FROM
THE SOUTH WHERE AN AREA OF MVFR CEILING RESIDES OVER INDIANA AND
OHIO. LIGHT PRECIPITATION MAY BRUSH THE MBS TERMINAL BUT THE
BOUNDARY LAYER WILL REMAIN WARM ENOUGH FOR ALL RAIN BEFORE SINCE THE
PRECIPITATION WILL BE MOSTLY EAST OF THE TERMINAL BEFORE THE COLD
FRONT ARRIVES. NORTHWEST WIND GUSTING TO AROUND 20 KNOTS WILL THEN
BRING DRY AND COLDER AIR INTO THE REGION THAT WILL LEAD TO A
DIMINISHING CLOUD TREND DURING THE AFTERNOON INTO SATURDAY NIGHT.
FOR DTW... INCONSISTENT COVERAGE OF VFR CEILING BELOW 5000 FT WILL
PRECEDE MVFR CEILING POISED TO DEVELOP NORTHWARD FROM INDIANA AND
OHIO BEFORE SUNRISE. THESE CLOUDS WILL MERGE WITH MVFR CEILING ALONG
AND BEHIND A COLD FRONT SET TO MOVE THROUGH DTW MID TO LATE MORNING.
A CLEARING TREND WILL THEN GET UNDERWAY DURING THE AFTERNOON AS DRY
AND COLDER AIR MOVES INTO THE REGION.
//DTW THRESHOLD PROBABILITIES...
* MODERATE FOR CEILING BELOW 5000 FT FOR THE REST OF TONIGHT THROUGH
EARLY AFTERNOON.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...DRK
LONG TERM....SC
MARINE.......SC
AVIATION.....BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DULUTH MN
654 PM CDT SUN MAR 22 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 312 PM CDT SUN MAR 22 2015
A COOL AND VERY DRY EAST FLOW OFF OF LAKE SUPERIOR HAS BEEN HELPING
TO KEEP TEMPERATURES IN THE 20S AND LOW 30S OVER THE NORTHLAND AND A
RIDGE OF HIGH PRESSURE WAS HELPING TO KEEP SKIES SUNNY. A BAND OF
SNOW AND FREEZING RAIN CONTINUED ACROSS SOUTHEAST NORTH
DAKOTA...SRN MN AND SOUTHWESTERN WISCONSIN. THIS KEEPS IT SOUTH OF
OUR WARNING AREA...WITH THE BAROCLINIC ZONE REMAINING JUST SOUTH
OF THE BRAINED LAKES AREA AND NORTH CENTRAL WI. HOWEVER...THIS IS
STILL A CHANCE THAT THERE MAY BE A GLANCING BLOW OF LIGHT SNOW TO
OUR FAR SOUTH...SO ALTHOUGH PULLED BACK CONSIDERABLY ON SNOW
CHANCES TONIGHT...DID NOT DELETE ALTOGETHER. THERE WILL BE A
CHANGE...HOWEVER...AS A STRONG UPPER LEVEL SHORT WAVE WILL MOVE
INTO THE THE REGION FROM CANADA. THIS POTENT SYSTEM WILL CAUSE
SNOW TO BREAK OUT OVER THE NORTHWEST LATE TONIGHT AND THEN SPREAD
EAST ACROSS THE ARROWHEAD. THERE WILL BE ENOUGH SYNOPTIC LIFT IN
THE SATURATED DGZ LAYER TO CREATE SOME GOOD DENDRITIC SNOW.
HOWEVER..THE SNOW WILL NOT LAST LONG WITH THIS FAST MOVING
SYSTEM...SO AMOUNTS SHOULD BE AN INCH OR LESS. WITH THE VORT MAX
DIVING SOUTHEAST ACROSS THE NORTHLAND...BROUGHT SOME LIGHT POPS TO
MUCH OF THE AREA MONDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 312 PM CDT SUN MAR 22 2015
CONCERN FOR LONG TERM IS STRONG SYSTEM AFFECTING AREA TUESDAY NIGHT
THROUGH THURSDAY.
MODELS ARE A LITTLE CLOSER WITH FORECAST SOLUTION BUT THE FORECAST
IS STILL A CHALLENGE. A WEAK RIDGE WILL GIVE THE REGION A PRECIP
FREE 24 HOURS BEFORE THE STRONG CLIPPER BEGINS TO AFFECT THE
FORECAST AREA TUESDAY EVENING. THE MODELS HAVE THE PLACEMENT OF THE
LOW CENTER IN SOUTHERN WISCONSIN WITH THE GEM HAVING OVER ARX TO NAM
PLACING IT OVER SOUTHERN LAKE MICHIGAN. ONE OF THE QUESTIONS OF THE
FORECAST IS THE AMOUNT OF SNOWFALL THAT AFFECT THE REGION WHICH WILL
BE AFFECTED BY THE TEMPS. THE ECMWF AND GFS GIVES THE REGION 4-7
INCHES WITH THE NAM PRODUCING AROUND 3-5 INCHES. ECMWF IS COLDER
THAN THE GFS AND THE NAM LEANING TOWARD THE GFS. ALSO...DENDRITIC
SNOW GROWTH WILL BE FAVORABLE ALONG THE NORTH SHORE AND ALONG A LINE
FROM THE TWIN PORTS TO HYR. WILL GO WITH A BLEND OF THE GFS AND
ECMWF WITH A LITTLE OF THE NAM.
TEMPS WILL FAVORABLE FOR ALL SNOW TUESDAY AND WEDNESDAY MORNING.
MOST AREAS WILL RECEIVE 2-4 INCHES WITH THE NORTH SHORE RECEIVING
3-5 INCHES. THESE SNOWFALL AMOUNTS WILL BE ADJUSTED WITH LATE MODEL
RUNS AS IT IS CLOSE BETWEEN THE TEMPS AND MOISTURE AMOUNTS. A
RAIN/SNOW MIXTURE WILL BE LIKELY WEDNESDAY AFTERNOON MAINLY SOUTH OF
HIGHWAY 2 AS TEMPS WARM. A COLD FRONT WILL MOVE THROUGH THE REGION
LATE WEDNESDAY AFTERNOON SWITCHING THE PRECIP BACK TO ALL SNOW.
SNOWFALL AMOUNTS WILL BE LOWER THAN THE TUESDAY NIGHT-WEDNESDAY
TIMEFRAME.
CYCLONIC FLOW WILL KEEP THE CHANCE FOR LIGHT SNOW ACROSS THE
FORECAST AREA WEDNESDAY NIGHT AND THURSDAY. HIGH PRESSURE BUILDS
INTO THE REGION THURSDAY NIGHT AND FRIDAY ENDING THE PRECIP.
ANOTHER SHORTWAVE MOVES THROUGH FRIDAY NIGHT BRINGING ANOTHER
POSSIBILITY OF SNOW SHOWERS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 654 PM CDT SUN MAR 22 2015
THE NORTHLAND WILL BE IMPACTED BY A COUPLE DIFFERENT SHORTWAVES
TONIGHT INTO MONDAY. THE FIRST ONE MAY BRING SOME LIGHT SNOW OR
FLURRIES TO FAR SOUTHERN AREAS...BUT SHOULD MISS KBRD/KHYR. VFR
CEILINGS WILL EXPAND ACROSS THE NORTHLAND TONIGHT...AND LAST INTO
MONDAY. THERE IS SOME INDICATION IN THE NAM THAT MVFR CEILINGS
WILL FORM AT KBRD/KDLH/KHYR LATE TONIGHT OR MONDAY MORNING.
HOWEVER...BASED ON THE RAP AND LATEST OBSERVATIONAL TRENDS WE DID
NOT BRING IN THESE CEILINGS YET. WE DID LOWER CEILINGS TO MVFR AT
KINL AND KHIB ON MONDAY DUE TO A NORTHERN STREAM WAVE. THERE WILL BE
SOME LIGHT SNOW THAT IMPACTS PORTIONS OF NORTHERN MINNESOTA. THE
LATEST GUIDANCE SUGGESTS THIS SNOW WILL DIMINISH AS IT PROGRESSES
EAST INTO MINNESOTA/NORTHWEST WISCONSIN. CONFIDENCE IS NOT
PARTICULARLY HIGH THAT THIS WILL OCCUR. WE MAY NEED TO ADD MORE
SNOW TO KBRD/KDLH/KHYR LATER MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 22 36 27 43 / 0 20 10 10
INL 21 38 27 46 / 10 50 10 10
BRD 25 43 28 45 / 30 10 10 10
HYR 22 43 26 47 / 10 20 10 10
ASX 22 39 26 47 / 0 20 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CLC
LONG TERM...STEWART
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
841 PM CDT SUN MAR 22 2015
.UPDATE...MAJORITY OF PRECIP HAS EXITED EAST...BUT THE EXCEPTION IS
OVER THE FAR NE WHERE SOME LIGHT RAIN AND DRIZZLE PERSIST. HAVE
REMOVED POPS FOR ALL AREAS EXCEPT FOR SLIGHT IN THE NE. ALSO...UPPED
MINS A LITTLE TONIGHT CLOSER TO THE HRRR SOLUTION AS PERSISTENT CLOUD
COVER AND ONLY WEAK COLD ADVECTION SHOULD LIMIT OVERALL COOLING
TONIGHT./26/
&&
.AVIATION...IFR/MVFR CIGS/VSBYS CONTINUE AT THE MOMENT WITH AREAS OF
DRIZZLE AND FOG...ESPECIALLY AROUND GTR/MEI/GLH/GWO. BELIEVE
CONDITIONS WILL SLOWLY IMPROVE FROM THE NW OVERNIGHT AS DRIER AIR
TRIES TO MOVE INTO THE LOWER LEVELS. THIS SHOULD ALLOW VSBYS TO
IMPROVE AS WELL AS CIGS TO RISE./26/
&&
.PREV DISCUSSION... /ISSUED 405 PM CDT SUN MAR 22 2015/
SHORT TERM...THIS FORECAST WILL MAINLY BE A CLOUD/TEMPS TYPE
FORECAST NOW THAT THE WIDESPREAD PRECIP HAS PUSHED OUT OF THE CWA.
WHILE THAT HAS MOVED ALONG...THERE STILL REMAINS SOME DECENT CHANCES
FOR SOME ACTIVITY. ACROSS THE FAR SE...ISO/SCT CONVECTION REMAINS
POSSIBLE UNTIL ABOUT 6PM AS THE UPPER FORCING COMBINES WITH A SMALL
ZONE OF INSTABILITY AND MOISTURE CONVERGENCE RIGHT ALONG THE
CONFLUENT AXIS OF THE WEAK SFC LOW. HERE...A STRONG STORM REMAINS A
POSSIBILITY UNTIL 6PM. OUTSIDE OF THAT SMALL AREA...SOME LOW END
CHANCE FOR SHOWERS EXIST. WHAT WILL MAINLY BRING THE BEST CHANCE TO
SEE SOME MEASURABLE LIGHT RAIN WILL BE AS THE UPPER COLD CORE MOVES
ACROSS THE N HALF OF THE AREA LATER THIS EVE INTO THE OVERNIGHT. AS
OF 3PM...THIS FEATURE IS GENERATING -RA AND DRIZZLE ACROSS MUCH OF
AR. LOOK FOR THIS TO SHIFT OVER OUR N SECTIONS LATER. I WOULD
TYPICALLY HAVE HIGHER POPS FOR THIS...BUT DEPTH OF MOISTURE OFFERS
SOME UNCERTAINTY FOR MEASURABLE PRECIP...THUS WILL KEEP THE 40-50%
GOING.
AS FOR TEMPS...MUCH OF THE AREA IS ON THE BACK (COOL SIDE) OF THE
SFC LOW AND WILL EXPERIENCE A CAA/CLOUDY REGIME TONIGHT. THE FAR SE
IS QUITE WARM NOW (77-80) BUT THEY TO WILL TRANSITION COOLER AS THE
WIND SHIFT OCCUR BY EARLY EVENING. OVERCAST CONDITIONS ARE EXPECTED
TO LINGER AS HIGH MOISTURE WILL EXIST IN THE 925-850MB LAYER AND BE
LOCATED WITH A LOW LEVEL THERMAL TROUGH. THIS IS THE PERFECT
RECIPE FOR LINGERING STRATUS WELL INTO MON. SOME CLEARING FROM THE
W/NW IS LIKELY BY AFTERNOON ON MON AS THE UPPER TROUGH AXIS SHIFTS
AWAY FROM THE REGION. STILL...SOME LOCATIONS MIGHT SEE CLOUDS HANG
TOUGH. CLOUDS WILL HAVE A HUGE IMPACT ON TEMPS TOMORROW AND HAVE
TRENDED MORE IN LINE WITH THE COOLER RAW BLENDS AS THEY SEEM TO
CAPTURE THE SITUATION BEST.
MONDAY NIGHT WILL ALSO BE INTERESTING AS LOCATIONS THAT SEE CLEAR
SKIES OR ANY CLEARING OVERNIGHT...WILL HAVE THE OPPORTUNITY TO COOL
INTO THE UPPER 40S. WET GROUND AND LINGERING BOUNDARY LAYER MOISTURE
LOOK TO SUPPORT FOG DEVELOPMENT.
LOOK FOR A WARMING TREND FOR TUE INTO WED AS THE AREA WILL BE IN
INCREASING SOUTHERLY RETURN FLOW AHEAD OF THE NEXT COLD FRONT. /CME/
LONG TERM...WEDNESDAY NIGHT THROUGH THURSDAY NIGHT - GULF MOISTURE
WILL BE SLOW TO RETURN AHEAD OF THE COLD FRONT. LIMITED MOISTURE
COMBINED WITH WEAK LIFT AND MOISTURE CONVERGENCE IN A FRONTOLYTIC
PATTERN WILL YIELD LIMITED CONVECTIVE RAINFALL.
FRIDAY THROUGH SUNDAY - GLOBAL MODELS AGREE THAT A SHARP NORTHERN
STREAM TROUGH WILL BRING A SURGE OF CHILLY POLAR AIR SOUTHWARD
THROUGH THE MS VALLEY. IT IS POSSIBLE THAT MUCH OF THE ARKLAMISS WILL
SEE A SIGNIFICANT FROST/FREEZE EVENT WHICH COULD HAVE BIG IMPACTS
GIVEN RECENT WARMTH AND START OF THE GROWING SEASON. MOS GUIDANCE IS
NOT GOING TO PICK UP ON THIS WELL SO FAR OUT DUE TO CLIMATOLOGY
INFLUENCES...AND HAVE CUT MOST VALUES BY SEVERAL DEGREES FOR THIS
FORECAST. JUST TO GIVEN AN IDEA OF THE POTENTIAL...SLU CIPS ANALOG
GUIDANCE CENTERED ON SATURDAY INDICATES 50-60% EXCEEDANCE OF THE <32F
FOR 5 HR THRESHOLD OVER EAST CENTRAL MS...AND > 50% EXCEEDANCE OF THE
<32F FOR 1 HR THRESHOLD FOR MOST OF THE FORECAST AREA. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 55 68 50 74 / 0 0 0 0
MERIDIAN 57 65 49 74 / 12 8 0 0
VICKSBURG 55 70 48 75 / 0 0 0 0
HATTIESBURG 57 67 51 78 / 10 3 0 0
NATCHEZ 54 69 50 74 / 0 0 0 0
GREENVILLE 52 70 48 74 / 0 0 0 0
GREENWOOD 52 70 49 75 / 10 0 0 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1149 PM CDT Fri Mar 20 2015
.UPDATE:
Issued at 715 PM CDT Fri Mar 20 2015
Cirrus clouds are much thicker than originally anticipated based
on ground obs and visible satellite before the sun went down. Have
boosted sky cover for this evening for most of the area with the
trend expected to be for the thicker cloud cover to sag south a
bit overnight. SW surface winds also won`t allow much of a temp
drop either and so edged min temps up a deg or two as well for
many areas. Only in the far northern CWA around UIN will the
forecast be relatively unaffected.
TES
&&
.SHORT TERM: (Through Tonight)
Issued at 250 PM CDT Fri Mar 20 2015
Focus tonight will be temps.
Clouds continue to struggle to dissipate this afternoon. It appears
the RAP is handling these clouds the best for now. Nrn edge of the
clouds shud continue slowly moving ewd. Further S, believe clouds
will continue to dissipate and move newd. A section of the nrn
clouds from near KCOU to KUIN will likely be the last to dissipate
or advect out of the area. Across the srn portions of the CWA, CI
has already begun to move into the area and will continue to do so
overnight. However, it is a little uncertain how thick these clouds
will be.
Have trended twd the cooler guidance tonight partially because of
anticipating the clearing. However, going forecast may not be cold
enuf since temps struggled today.
Tilly
.LONG TERM: (Saturday through Next Friday)
Issued at 250 PM CDT Fri Mar 20 2015
A cdfnt shud have arrived across the nrn third of the CWA by 12z
Sat. This fnt will continue to push swd thru the day. While this may
be a cold fnt, with nearly full insolation expected, tomorrow shud
actually be warmer than today. Mdls also push the thermal ridge
across the region on Sat. The fnt begins to lift nwd on Sun as a sfc
low and associated s/w approach the region. While not high chances,
this system will bring a chance for RA across nrn portions of the
CWA Sun night and across much of the area on Mon, more probable
during the afternoon with heating.
As the trof deepens across the Plains and the LLJ increases with
what shud be an open Gulf, precip chances increase quickly Mon night
and Tues, with TS becoming more probable as well. Going forecast
PoPs may be too low attm, but have not gone higher for now due to
lack of persistence among mdl guidance. Given the amount of shear
available with the system on Tues, there is a very narrow window
where severe weather potential exists. However, given a number of
questions regarding timing with this event, will hold off mention in
products now other than that it remains to be a system to watch.
Behind the cdfnt late Wed and a secondary cdfnt on Thurs, the
potential for a very cold rain or possibly even light snow event
exists. Have kept as RA for now, but again, will be a system to
monitor.
Tilly
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1135 PM CDT Fri Mar 20 2015
Cirrus is expected to continue to stream ENE from the sthrn
Plains thru the fcst prd...esp across sthrn MO and sthrn IL. There
may still be some MVFR fog towards 12Z...but the thick cirrus may
limit fog potential with KUIN being the exception since they are
north of the densest cloud cover. A weak bndry will push thru the
area Sat mrng causing winds to go from S/SW sat mrng to NE by late
aftn as a sfc ridge noses into the Grt Lks region out of Canada.
Winds are expected to remain aob 10kts.
Specifics for KSTL:
VFR fcst thru the prd. Removed the high end MVFR fog with current
thinking that the thick cirrus expected for the rest of the night will
hold temps up enough so the cross over temp is not reached. Otherwise
expect a slowly backing wind from mid mrng thru the aftn as a weak
cold front slides thru.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1123 PM CDT FRI MAR 20 2015
.SYNOPSIS...
ISSUED AT 340 PM CDT FRI MAR 20 2015
H5 ANALYSIS FROM EARLIER THIS MORNING CONTINUES TO
INDICATE RIDGING ACROSS THE WESTERN CONUS WITH A CUTOFF LOW OVER
PORTIONS OF SOUTHERN BAJA CALIFORNIA. A DECENT SHORTWAVE WAS NOTED
OVER SRN COLORADO. NORTH OF THE BORDER...LOW PRESSURE WAS NOTED OVER
HUDSON BAY AND A SECOND LOW WAS NOTED SOUTH OF GREENLAND. ANOTHER
LOW WAS LOCATED SOUTH OF THE ALEUTIANS OF ALASKA WITH A TANDEM OF
SHORTWAVES ON THE SRN AND SERN PERIPHERY OF THIS FEATURE. WV IMAGERY
FROM THIS AFTERNOON IS INDICATING A NICE PLUME OF UPPER LEVEL
MOISTURE...STREAMING INTO THE PACIFIC NORTHWEST AND THE CANADIAN
ROCKIES. ANOTHER AREA OF ABUNDANT HIGH LEVEL MOISTURE WAS NOTED FROM
MEXICO INTO TEXAS AND THE SERN STATES. ACROSS THE CENTRAL
CONUS...DRYING WAS NOTED WITH CLEAR SKIES IN PLACE ACROSS WESTERN
AND NORTH CENTRAL NEBRASKA. AT THE SURFACE...LOW PRESSURE WAS
LOCATED OVER CENTRAL NORTH DAKOTA WITH A DECENT TROUGH OF LOW
PRESSURE EXTENDING SWD INTO CENTRAL AND SRN NEBRASKA. WINDS WERE
FROM THE WEST AND WEST SOUTHWEST AT 10 TO 20 MPH THIS
AFTERNOON...WITH A FEW GUSTS TO 30 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 340 PM CDT FRI MAR 20 2015
CLEAR SKIES AND LIGHT WINDS ARE EXPECTED TONIGHT. A WEAK BACK DOOR
COLD FRONT WILL TRY TO PUSH SOUTHWEST INTO THE AREA...AND SHOULD
PUSH THROUGH THE ONEILL AREA AND STALL ALONG A LINE FROM BROKEN BOW
TO AINSWORTH LATE TONIGHT. THE ONLY NOTICEABLE DIFFERENCE ASSOCIATED
WITH THE FRONT WILL BE A SHIFT IN THE WIND TO LIGHT NORTHEAST AS THE
FRONT PASSES. TEMPERATURES WILL REALLY NOT BE MUCH DIFFERENT ON
EITHER SIDE OF THE FRONT.
A SHORTWAVE TROUGH WILL MOVE INTO MONTANA FROM THE WEST LATER
SATURDAY. AHEAD OF THIS FEATURE...SURFACE LOW PRESSURE WILL DEEPEN
AND MOVE EAST ALONG THE NE/SD BORDER DURING THE DAY. A WARM FRONT
WILL EXTEND SOUTHEAST FROM THE LOW CENTER...AND WILL ADVANCE EAST
ACROSS THE AREA DURING THE DAY SATURDAY. BOTH THE NAM AND GFS ARE IN
GOOD AGREEMENT AND HAVE THE LOW NEAR VALENTINE BY LATE
AFTERNOON...WITH THE WARM FROM ARCING SOUTHEAST FROM THE LOW CENTER
TOWARD BROKEN BOW. TO THE EAST OF THE WARM FRONT...WINDS WILL REMAIN
BACKED A BIT TO THE SOUTHEAST...WITH TEMPERATURES PROBABLY NOT
REACHING MUCH ABOVE 65 DEGREES. TO THE WEST OF THE WARM
FRONT...SOUTHWEST TO WESTERLY DOWNSLOPE WEST WINDS WILL COMBINE WITH
A PLUME OF WARM AIR ALOFT /H850MB TEMPS NEAR 17C/ WITH HIGHS WELL
INTO THE 70S. SOUNDING PROFILES INDICATE A DEEPLY MIXED
ATMOSPHERE...SO THINK A FIRE WEATHER WATCH IS NEEDED FOR AREAS ALONG
AND WEST OF THE WARM FRONT ACROSS WESTERN NEBRASKA. WINDS MAY BE
MARGINAL...BUT WITH THE VERY DRY AIR AND DEEP MIXING FEEL A WATCH IS
NEEDED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 340 PM CDT FRI MAR 20 2015
MID RANGE...SATURDAY NIGHT THROUGH MONDAY...FOR SATURDAY NIGHT
THROUGH MONDAY...TEMPERATURES WILL BE THE MAIN FORECAST CHALLENGE.
ON SATURDAY NIGHT...SURFACE LOW PRESSURE WILL TRACK FROM THE
PANHANDLE INTO CENTRAL PORTIONS OF THE FORECAST AREA. WITH THE LOW
OVER CENTRAL PORTIONS OF THE FORECAST AREA...LOW LEVEL MOISTURE WILL
BE SHOVED EAST OF THE FORECAST AREA...WHICH WILL ALLOW MINS TO DROP
OFF INTO THE 30S SATURDAY NIGHT. IF THE LOW CONTINUES TO TREND
FARTHER EAST...WILL NEED TO DROP LOWS A BIT FURTHER AS DRIER AIR
WILL BE DRAWN FURTHER EAST FROM THE PANHANDLE. ON SUNDAY...LOW
PRESSURE WILL DROP SOUTH INTO KANSAS WITH A COLD FRONT EXTENDING
FROM SERN NEBRASKA INTO SWRN KS. WINDS WILL BE GUSTY INITIALLY
BEHIND THE FRONT WITH DECREASING WINDS IN THE AFTERNOON HOURS.
YESTERDAY...WAS CONCERNED SOME ABOUT HAZARDOUS FIRE DANGER CONDS
SUNDAY AFTERNOON...HOWEVER...BOTH THE NAM AND GFS THIS MORNING HAVE
DEW POINTS IN THE 20S BEHIND THE FRONT...WHICH IS A SLIGHT INCREASE
FROM YESTERDAY. ALSO...HIGHS TRENDED A LITTLE COOLER AS WELL...SO
MIN RH/S ARE NOT AS CRITICAL NOW. ATTM...DECIDED TO TREND HIGHS
SUNDAY A TAD COOLER WITH UPPER 50S IN THE NORTHEAST TO UPPER 60S IN
THE FAR SOUTHWEST. ON SUNDAY NIGHT...MID LEVEL WARM AIR ADVECTION
WILL BEGIN TO INCREASE IN THE PANHANDLE AND NORTHWEST OVERNIGHT
LEADING TO INCREASED CLOUDINESS AND AN OUTSIDE CHANCE OF A SHOWER IN
THE NORTHWEST. ON MONDAY SURFACE LOW PRESSURE WILL CONTINUE TO
DEEPEN ACROSS EASTERN WYOMING...LEADING TO INCREASED SOUTHEASTERLY
FLOW FLOW. WITH AN EASTERLY COMPONENT TO THE LOW LEVEL WINDS MONDAY
AND INCREASED LOW LEVEL MOISTURE ADVECTION...DECIDED TO DROP HIGHS A
TAD MONDAY FROM THE INHERITED FCST. THIS YIELDED HIGHS IN THE 60S
ACROSS THE FORECAST AREA.
LONG TERM...MONDAY NIGHT THROUGH FRIDAY...DECENT LOW LEVEL MOISTURE
ADVECTION WILL CONTINUE MONDAY NIGHT WITH DEW POINTS REACHING THE
LOWER 40S ACROSS THE EASTERN 2/3RDS OF THE FORECAST AREA OVERNIGHT.
A LEAD SHORTWAVE WILL APPROACH THE PANHANDLE LATE MONDAY
NIGHT...LEADING TO INCREASED ELEVATED INSTABILITY. AS WAS THE CASE
YESTERDAY...H850 LI/S RANGE FROM 0 TO -2C ACROSS THE EASTERN 2/3RDS
OF THE FORECAST AREA LATE MONDAY NIGHT. INHERITED FCST HAD A MENTION
OF THUNDER AND WILL KEEP THIS INTACT WITH THE AFTERNOON PACKAGE. ON
TUESDAY...SURFACE LOW PRESSURE WILL QUICKLY LIFT INTO SOUTH DAKOTA
BY MIDDAY...FORCING THE DRYLINE INTO EASTERN NEBRASKA BY 18Z. STILL
HELD ONTO SOME SLIGHT CHANCE POPS...FOR ANY RESIDUAL THUNDERSTORMS
TUESDAY MORNING. THE AFTERNOON WILL BE DRY AND WINDY...AND WILL
LIKELY NEED SOME SORT OF FIRE HEADLINE...ESPECIALLY IN THE WEST
WHERE SFC DEW POINTS REACH THE SINGLE DIGITS BY TUESDAY AFTERNOON.
WILL CONTINUE TO HIT THE FIRE DANGER TUESDAY HARD IN THE HWO SINCE
CONFIDENCE CONTINUES TO INCREASE IN THIS HAPPENING. BEYOND
TUESDAY...THE PATTERN WILL BEGIN TO AMPLIFY ACROSS THE CONUS WITH
RIDGING ACROSS THE WESTERN THIRD OF THE CONUS AND A DEEPENING TROUGH
OVER THE GREAT LAKES SWD TO THE NRN GULF COAST. ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA...MUCH COOLER TEMPS WILL ARRIVE ON WEDNESDAY
AND WILL PERSIST THROUGH FRIDAY. WITH THE MODELS TRENDING TOWARD A
DRIER PATTERN LATE NEXT WEEK...WILL LEAVE THE FCST DRY BEYOND
TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1122 PM CDT FRI MAR 20 2015
VFR IS EXPECTED ALL AREAS OVERNIGHT THRUOGH SATURDAY EVENING.
A WEAK COLD FRONT LOCATED IN THE PLATTE VALLEY WILL BE LIFTED
NORTH AS LOW PRESSURE ACROSS THE NRN HIGH PLAINS TRACKS INTO
NEBRASKA SATURDAY AND SATURDAY NIGHT. GENERALLY CLEAR SKIES ARE
EXPECTED DURING THIS TIME.
&&
.FIRE WEATHER...
ISSUED AT 756 PM CDT FRI MAR 20 2015
WINDS HAVE DECREASED AS EXPECTED AND THE RED FLAG WARNING HAS BEEN
ALLOWED TO EXPIRE.
THE STRONGER WIND SPEEDS SATURDAY AFTN APPEAR TO BE NORTH OF
INTERSTATE 80 AND GENERALLY ALONG AND EAST OF HIGHWAY 61
SUGGESTING RED FLAG CONDITIONS ARE MOST LIKELY IN THIS AREA. THIS
IS BASED ON A MULTI MODEL BLEND APPROACH. THERE ARE NO STAND OUT
SOLNS EXCEPT FOR THE GEM REGIONAL WHICH SHOWED THE STRONGEST WINDS.
TONIGHTS MODEL RUNS AND THE RAP MAY TREND TOWARD THE GEM MODEL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
EVENING FOR NEZ204-206-210-219.
&&
$$
SYNOPSIS...CLB
SHORT TERM...TAYLOR
LONG TERM...CLB
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
310 PM MDT SAT MAR 21 2015
.SYNOPSIS...
DRYING AND WARMING TREND SUNDAY AND MONDAY WITH SOME AFTERNOON
WINDINESS MONDAY. CRITICAL FIRE WEATHER CONDITIONS COULD DEVELOP
MONDAY AFTERNOON FROM THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN
OVER THE NORTHEAST AND EAST CENTRAL PLAINS. SOMEWHAT COOLER
TUESDAY...ALTHOUGH HIGH TEMPERATURES WILL REMAIN ABOVE AVERAGE.
THERE IS POTENTIAL FOR A BRIEF PERIOD OF WETTER WEATHER AROUND THE
MIDDLE OF NEXT WEEK...BUT FORECAST MODELS DIFFER CONSIDERABLY. A
DRYING TREND LOOKS TO RETURN FOR NEXT FRIDAY AND SATURDAY.
&&
.DISCUSSION...
PUNY CONVECTION OVER SOME OF THE NORTHERN...WESTERN AND CENTRAL
HIGH TERRAIN THIS AFTERNOON. KEPT THE SMALL INHERITED POPS FOR THIS
EVENING WITH LITTLE CHANGE...ALTHOUGH BOTH HRRR AND NAM12 MAKE A
CASE FOR ISOLATED CELLS THIS EVENING OVER THE FAR NORTHEAST. GIVEN
THERE/S NOT MUCH GOING ON OVER THE MTS ON THE COLORADO SIDE OF THE
BORDER AT THE MOMENT...THERE/S PROBABLY NOT MUCH CHANCE FOR ONE TO
SCORE A DIRECT HIT ON ANY RAINFALL MEASURING BUCKET.
OTHERWISE...THERE IS POTENTIAL FOR AT LEAST PATCHY FOG IN THE PECOS
VALLEY SOUTH OF INTERSTATE 40 EASTWARD TO THE TEXAS BORDER LATER
TONIGHT AND EARLY SUNDAY...INCLUDING THE CLOVIS/PORTALES
AREA...WHERE 40S DEWPOINTS FORECAST TO REMAIN IN PLACE AND THE MID
TO HIGH LEVEL MOISTURE CLEARS OUT WITH THE DEPARTING LOW/TROUGH.
DEW POINTS DRY OUT SUNDAY AS AN WEAK RIDGE BUILDS OVER THE STATE. A
SFC LEE TROUGH WILL BE ESTABLISHED...AND TEMPERATURES WILL RANGE
FROM AROUND 5 TO NEARLY 20 DEGREES ABOVE AVERAGE...WITH THE GREATEST
DEVIATION FROM NORMAL ACROSS NORTH CENTRAL AND NORTHEAST.
A TREND TOWARD ZONAL FLOW MONDAY...AND COMBINED WITH THE SFC
TROUGH...BREEZY TO WINDY CONDITIONS LOOK TO DEVELOP ESPECIALLY FROM
THE CENTRAL MT CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS.
WIDESPREAD WIND ADVY CRITERIA DOESN/T APPEAR TO BE
LIKELY...HOWEVER...IMPACTS WILL BE FIRE WEATHER RELATED AS HIGHS
WILL SOAR IN TO THE UPPER 70S AND 80S MONDAY AFTERNOON OVER THAT
PART OF THE FORECAST AREA. HIGH TEMPERATURE DEVIATIONS FROM AVERAGE
WILL BE SOMEWHAT SIMILAR TO THOSE OF SUNDAY.
TUESDAY WILL BE SLIGHTLY COOLER AS THE SFC TROUGH AND ASSOCIATED
SHORT WAVE TRACK NORTHEAST OF NEW MEXICO...LEAVING SOME GUSTY
NORTHWEST WINDS TO AFFECT THE CENTRAL MT CHAIN AND ADJACENT
HIGHLANDS.
FOR THE MID TO LATE WEEK PERIOD...THE ECMWF REMAINS THE WETTER
MODEL...COMPARED TO THE GFS...WHICH DEVELOPS 2 SEPARATE FEATURES...A
CUTOFF LOW OVER SOCAL...AND A SHORT WAVE IN THE NW FLOW ALOFT WHICH
CLIPS NORTHEAST NM. GIVEN THE DIFFERENCES...REINED IN POPULATED POPS
FOR WED NIGHT/THURS. FRIDAY AND SATURDAY LOOK DRY...BUT ECMWF DROPS
ANOTHER SHORT WAVE INTO NORTHERN NEW MEXICO SUNDAY...WHILE THE GFS
BOOTS OUT THE SOCAL LOW FARTHER NORTH AND OVER THE STATE. EITHER
WAY...IT LOOKS LIKE SPOTTY PRECIPITATION COULD DEVELOP.
&&
.FIRE WEATHER...
...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE ON MONDAY ACROSS MUCH
OF EASTERN NEW MEXICO...
LOW PRESSURE SYSTEM ALOFT CONTINUES TO SWING SOUTH OF NM TODAY WITH
SOME STEADY BATCHES OF LIGHT PRECIPITATION FAVORING THE SOUTHERN
TIER OF THE STATE...MOSTLY OUT OF THE ABQ FIRE WEATHER FORECAST
AREA. HOWEVER...SOME REMNANT INSTABILITY AND MOISTURE IS LEADING TO
DEVELOPMENT OF NEW SHOWERS AND STORMS OVER THE HIGHER TERRAIN OF
CENTRAL NM THIS AFTERNOON. THIS ACTIVITY SHOULD REMAIN FAIRLY
ISOLATED WITH LOW PROBABILITIES FOR ACTUAL WETTING RAINFALL...BUT A
FEW CLOUD TO GROUND LIGHTNING STRIKES COULD OCCUR. DRIER AIR IN THE
MID TO UPPER LEVELS OF THE ATMOSPHERE IS SLOWLY FILTERING INTO THE
STATE FROM THE NORTH NORTHWEST...AND THIS TREND WILL PERSIST
OVERNIGHT. HOWEVER...THE DEWPOINTS NEAR THE SURFACE WILL BE SLOWER
TO RESPOND TO THIS DRYING...THUS ANOTHER NIGHT/MORNING OF EXCELLENT
RH RECOVERY IS ANTICIPATED THROUGH EARLY SUNDAY.
THE REMNANTS OF THE LOW PRESSURE SYSTEM WILL HAVE FULLY EXITED EAST
OF NM ON SUNDAY...GIVING WAY TO A RIDGE OF HIGH PRESSURE. THIS WILL
KEEP THE DRYING TREND GOING...WITH LOW LAYER RH/DEWPOINTS ALSO
QUICKLY RESPONDING DOWNWARD AS DEEP MIXING ENSUES IN AN ABOVE NORMAL
TEMPERATURE REGIME. PRECIPITATION WILL HAVE FULLY ESCAPED AND THE
ENTIRE FORECAST AREA SHOULD EXCEED SEASONAL AVERAGES. A WEAK LEE
SIDE SURFACE TROUGH WILL STRUGGLE TO TAKE SHAPE...BUT WILL NOT FULLY
COME TOGETHER BEFORE DUSK SUNDAY.
THE PATTERN TURNS MORE CRITICAL ON MONDAY AS THE RIDGE ALOFT BREAKS
DOWN AND STRONGER WESTERLY FLOW ALOFT DEVELOPS OVER NM WITH AVERAGE
SPEEDS OF 30-40 MPH IN THE 10000 TO 18000 FT LAYER. THIS WILL BE A
NOTABLE STRENGTHENING OF THESE UPPER LEVEL WINDS THAT HAS YET TO
TRANSFER TO THE SURFACE THUS FAR THIS YEAR. AS THE LEE SIDE SURFACE
CYCLONE BECOMES BETTER ESTABLISHED EXCELLENT MIXING IS
FORECAST...AND BREEZY TO WINDY CONDITIONS WILL ENSUE MONDAY
AFTERNOON WHILE THE WARMER THAN AVERAGE AND DRY CONDITIONS PERSIST.
WIND SPEEDS LOOK TO EXCEED CRITICAL SPEEDS OVER MUCH OF THE
NORTHEASTERN QUADRANT OF NM WHERE RH WILL PLUMMET TO 10 TO 15
PERCENT MONDAY AFTERNOON...AND AFTER FURTHER COLLABORATION ON THE
STATUS OF THE FINE OR 1-HOUR FUELS...BELIEVE THERE WILL BE ENOUGH
FIRE DANGER JUXTAPOSED WITH THE CRITICAL WINDS/RH. THUS...A WATCH
WILL BE HOISTED WITH THIS FORECAST PACKAGE.
A SHORT WAVE TROUGH WILL PASS NORTH OF NM MONDAY NIGHT...KEEPING
WINDS ALOFT STRONG...AND SOME MOUNTAIN WAVE ACTIVITY MAY EVEN CRASH
EAST OF THE SANGRE DE CRISTOS INTO EARLY TUESDAY MORNING. THE
REMAINDER OF TUESDAY SHOULD SEE A DECREASE IN SPEEDS ALOFT WITH
SLIGHTLY COOLER...BUT STILL ABOVE AVERAGE TEMPERATURES PREVAILING.
THE NEXT NOTABLE FEATURE WILL APPROACH ON THURSDAY AS A TROUGH DIVES
SOUTHEAST OUT OF CANADA AND ADDITIONAL ENERGY SEPARATES AND CUTS OFF
ON A TRAJECTORY NEAR OR WEST OF NM. FORECAST MODELS ARE HAVING
DIFFICULTY RETAINING CONTINUITY BETWEEN RUNS AND AMONGST EACH OTHER.
THE IMPACTS FROM THE COLDER AIR AND PRECIPITATION SEEM LESS CERTAIN
ACCORDING TO THE GFS...WHILE THE EUROPEAN MODEL IS MORE ASSERTIVE
WITH BOTH.
52
&&
.AVIATION...
18Z TAF CYCLE
NEW CUMULUS CLOUDS ARE STARTING TO BUBBLE UP OVER THE HIGHER
TERRAIN OF CENTRAL TO WESTERN NEW MEXICO EARLY THIS
AFTERNOON...AND ISOLATED TO SCATTERED SHOWERS ARE EXPECTED TO TAKE
SHAPE INTO THE MID AFTERNOON. ACTIVITY WILL GENERALLY DRIFT FROM
NORTHWEST TO SOUTHEAST AT ABOUT 10 TO 15 MPH WITH GUSTY OUTFLOW
WINDS AND SMALL HAIL POSSIBLE. ANY REDUCTIONS TO
CEILINGS/VISIBILITIES IN DOWNPOURS WILL BE VERY BRIEF. THERE IS
POTENTIAL FOR SOME LOW STRATUS CLOUDS/FOG TO DEVELOP IN THE PECOS
VALLEY AND TOWARD THE EAST CENTRAL PLAINS OF NEW MEXICO LATE
TONIGHT AND INTO EARLY SUNDAY MORNING. LOCALIZED MVFR TO IFR/LIFR
CONDITIONS WOULD BE POSSIBLE...GENERALLY EAST OF A KROW TO KCVN
LINE.
52
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 35 71 34 70 / 0 0 0 0
DULCE........................... 31 67 28 64 / 5 0 5 0
CUBA............................ 34 67 32 65 / 0 0 0 0
GALLUP.......................... 26 69 25 68 / 0 0 0 0
EL MORRO........................ 29 65 28 63 / 5 0 0 5
GRANTS.......................... 27 69 24 67 / 0 0 0 0
QUEMADO......................... 30 66 29 66 / 0 0 0 0
GLENWOOD........................ 39 73 39 72 / 0 0 0 0
CHAMA........................... 22 60 24 57 / 10 0 5 5
LOS ALAMOS...................... 37 67 37 66 / 10 0 0 0
PECOS........................... 33 67 35 64 / 5 0 0 0
CERRO/QUESTA.................... 25 65 26 63 / 5 0 0 5
RED RIVER....................... 24 53 26 51 / 10 5 5 5
ANGEL FIRE...................... 26 59 22 57 / 5 5 0 5
TAOS............................ 28 67 28 65 / 5 0 0 0
MORA............................ 31 66 31 65 / 5 0 0 0
ESPANOLA........................ 37 72 35 71 / 0 0 0 0
SANTA FE........................ 37 66 39 65 / 5 0 0 0
SANTA FE AIRPORT................ 33 70 35 69 / 0 0 0 0
ALBUQUERQUE FOOTHILLS........... 37 72 40 70 / 0 0 0 0
ALBUQUERQUE HEIGHTS............. 38 73 41 72 / 0 0 0 0
ALBUQUERQUE VALLEY.............. 38 76 37 75 / 0 0 0 0
ALBUQUERQUE WEST MESA........... 39 75 38 73 / 0 0 0 0
LOS LUNAS....................... 35 77 35 76 / 0 0 0 0
RIO RANCHO...................... 39 75 38 73 / 0 0 0 0
SOCORRO......................... 40 77 41 77 / 0 0 0 0
SANDIA PARK/CEDAR CREST......... 37 70 39 69 / 0 0 0 0
TIJERAS......................... 34 73 35 71 / 0 0 0 0
MORIARTY/ESTANCIA............... 28 71 31 70 / 0 0 0 0
CLINES CORNERS.................. 34 69 36 68 / 5 0 0 0
GRAN QUIVIRA.................... 33 70 35 70 / 0 0 0 0
CARRIZOZO....................... 35 73 39 72 / 5 0 0 0
RUIDOSO......................... 34 68 40 68 / 10 0 0 0
CAPULIN......................... 33 70 32 71 / 5 0 5 0
RATON........................... 29 73 31 73 / 5 0 5 0
SPRINGER........................ 32 72 33 73 / 5 0 0 0
LAS VEGAS....................... 31 70 34 69 / 0 0 0 0
CLAYTON......................... 36 79 42 79 / 5 0 5 0
ROY............................. 36 75 38 75 / 5 0 5 0
CONCHAS......................... 40 79 40 81 / 0 0 0 0
SANTA ROSA...................... 39 77 41 78 / 0 0 0 0
TUCUMCARI....................... 40 81 40 83 / 0 0 0 0
CLOVIS.......................... 39 77 41 81 / 5 0 0 0
PORTALES........................ 41 76 40 81 / 5 0 0 0
FORT SUMNER..................... 41 79 41 81 / 0 0 0 0
ROSWELL......................... 42 81 42 85 / 10 0 0 0
PICACHO......................... 39 76 40 77 / 10 0 0 0
ELK............................. 37 71 40 72 / 20 0 0 0
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ103-104-107-108.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1028 PM EDT SUN MAR 22 2015
.SYNOPSIS...
VERY COLD TEMPERATURES AND GUSTY NORTHWEST WINDS WILL CONTINUE
ACROSS THE NORTH COUNTRY THROUGH MONDAY AS THE EFFECTS OF
YESTERDAYS ARCTIC COLD FRONT REMAIN. A FEW FLURRIES ARE POSSIBLE
THIS EVENING AND AGAIN MONDAY AFTERNOON BUT OVERALL CONDITIONS
WILL BE PREDOMINATELY DRY. HIGH PRESSURE WILL SETTLE OVER THE AREA
ON TUESDAY, BRINGING SUNNY SKIES AND MODERATING TEMPERATURES. A
WARM FRONT WILL BRING EVEN WARMER TEMPERATURES AND CHANCES FOR
RAIN LATE WEDNESDAY INTO THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 1021 PM EDT SUNDAY...MINOR TWEAKS BASED UPON LATE EVENING
SATELLITE/RADAR/SURFACE OBSERVATIONS. HAVE A FEW PATCHES OF CLOUDS
MOVING ACROSS THE REGION, WHICH PRODUCED A BRIEF PERIOD OF LIGHT
SNOW AT SARANAC LAKE AND LIKELY A FEW FLURRIES ELSEWHERE. HOWEVER,
THE TREND SEEMS FOR THE CLOUDS TO BE SLOWLY DISSIPATING. SECONDARY
SURGE OF COLD AIR LOOKS LIKE IT`S JUST ABOUT ALONG AN OTTAWA-
MONTREAL LINE AND PUSHING SOUTH-SOUTHEAST. MADE SOME MINOR ADJUSTMENTS
TO THE WINDS BASED ON 21Z 6KM LOCAL WRF RUN AND 01Z RAP OUTPUT.
BASICALLY AS THIS SURGE COMES THROUGH BETWEEN 04-07Z, WINDS WILL
PICK BACK UP AND REMAIN GUSTY INTO MONDAY MORNING. THIS WILL BE
WHEN WE`LL SEE OUR LOWEST WIND CHILLS.
REMAINDER BELOW IS FROM THE DISCUSSION A LITTLE EARLIER THIS
EVENING...
FORECAST PRETTY MUCH ON TRACK HERE AT MID-EVENING. WATCHING AREAS
OF CLOUDS FILLING IN ACROSS NORTHERN SECTIONS IN ASSOCIATION WITH
MID-LEVEL TROUGH AND ASSOCIATED COLD POOL -- WHICH BY THE WAY WITH
IT`S ROUGHLY -25C @ 850MB TEMPERATURES IS THE **COLDEST IN ALL OF
THE NORTHERN HEMISPHERE**. COLD AIR ALOFT IS MAKING FOR A SMALL
BIT OF LOW LEVEL INSTABILITY, AND ENVIRONMENT CANADA RADARS
SHOWING SHOWERY/CONVECTIVE NATURE OF THE PRECIPITATION UPSTREAM.
HOWEVER, SURFACE OBS INDICATE THE PRECIPITATION IS VERY LIGHT
(NOTHING MUCH MORE THAN FLURRIES) GIVEN THE VERY DRY LOW LEVELS.
RELATIVE HUMIDITY VALUES 30-45%. THUS FEEL ANY SNOW THAT FALLS
WILL BE NOTHING MORE THAN A BRIEF FLURRY. ACCUMULATIONS A DUSTING
AT MOST -- AND THAT WOULD PROBABLY BE UP IN THE ADIRONDACKS THANKS
TO SOME OROGRAPHIC ENHANCEMENT.
WINDS MAY DIMINISH A BIT FOR A FEW HOURS LATE THIS EVENING, THEN
PICK UP AGAIN WITH GUSTS 20-25KT OR SO AS THE TROUGH AND
ASSOCIATED WEAK WIND SHIFT PUSH SOUTHWARD ACROSS THE REGION. THUS
WIND CHILL ADVISORY STILL LOOKS ON TRACK FOR APPARENT TEMPERATURE
READINGS DROPPING LOWER THAN -20F IN THE `DACKS AND NORTH-
CENTRAL/NORTHEAST VERMONT LATE TONITE AND FIRST THING MONDAY
MORNING.
A FEW RECORDS COULD ADDITIONALLY BE SET FOR MIN TEMPS TONIGHT. A
FEW LOCATIONS HAVE RECORD RIGHT AROUND THE ZERO MARK WHICH IS
CLOSE TO MY OFFICIAL FORECAST. CHECK THE CLIMATE SECTION BELOW FOR
THOSE NUMBERS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 337 PM EDT SUNDAY...PRETTY QUICK WEATHER IS EXPECTED ACROSS
THE FORECAST AREA FOR THE SHORT TERM AS STRONG HIGH PRESSURE SOUTH
OF JAMES BAY EARLY MONDAY MORNING DRIFTS THROUGH THE NORTHEAST
MONDAY AND TUESDAY. OUTSIDE OF A FEW SNOW SHOWERS AND/OR FLURRIES
ACROSS THE HIGH PEAKS OF NORTHERN VERMONT TOMORROW, DRY CONDITIONS
ARE EXPECTED THROUGH THE PERIOD WITH WINDS TRENDING LIGHT. IT WILL
STILL BE RATHER COLD FOR LATE MARCH MONDAY AND MONDAY NIGHT AND WE
COULD SEE SOME LOW MAX TEMPERATURE RECORDS BROKEN TOMORROW AS
HIGHS WILL ONLY PEAK IN THE TEENS TO LOWER 20S. IN GENERAL, LOWS
MONDAY NIGHT WILL BE ABOUT 5 DEGREE WARMER THAN SUNDAY NIGHT,
STILL VERY COLD, BUT AS WE MOVE INTO TUESDAY HIGH PRESSURE MOVES
DIRECTLY OVERHEAD AND TUESDAY NIGHT EASTWARD OVER THE NEW ENGLAND
COAST. THIS WILL ALLOW TEMPERATURE TO MODERATE A BIT WARMING INTO
THE 20S AND 30S TUESDAY AND GENERALLY ONLY FALLING INTO THE TEENS
FOR TUESDAY NIGHT. A FEW LOCATIONS ACROSS THE ADIRONDACKS AND
NORTHEAST VERMONT COULD STILL SEE A FEW SINGLE DIGIT LOWS THOUGH.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 337 PM EDT SUNDAY...GOOD CONSISTENCY BETWEEN GFS/GFS
ENSEMBLE MEAN/ECMWF WITH THE 12Z CYCLE...AND FORECAST IS GENERALLY
CONSISTENT WITH EXPECTATIONS FROM THE PREVIOUS FEW SHIFTS.
SURFACE HIGH PRESSURE EXPECTED TO DEPART EAST OF NEW ENGLAND DURING
THE DAY WEDNESDAY...WITH DEVELOPMENT OF MODERATE S-SWLY WINDS. THESE
SOUTHERLY WINDS WILL HELP TEMPERATURES MODERATE INTO THE MID 40S
AREAWIDE BY AFTERNOON. MEANWHILE...LOW PRESSURE TRACKING EWD FROM
THE GREAT LAKES AND ASSOCIATED WARM FRONT WILL BRING INCREASING MID-
UPPER LEVEL ACROSS THE NORTH COUNTRY DURING THE DAY. LEANED TOWARD
12Z OPERATIONAL GFS TIMING WITH DEVELOPMENT OF SCATTERED RAIN
SHOWERS ACROSS THE REGION BY LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING. MAY SEE SOME WET SNOW AT THE ONSET ACROSS THE HIGHER
ELEVATIONS...WITH A LIGHT SNOW ACCUMULATION (D-2") GENERALLY ABOVE
2000`.
SURFACE LOW AND LOW-LEVEL WAA PASS TO OUR NORTH AND EAST DURING
WEDNESDAY NIGHT. CONTINUED S-SW WINDS AND OVERCAST CONDITIONS WILL
KEEP TEMPERATURES ABOVE FREEZING OVERNIGHT WEDNESDAY NIGHT. MAY SEE
A FEW RAIN SHOWERS DURING THE PERIOD. LOWS WILL RANGE FROM THE MID
30S EAST OF THE GREEN MTNS...TO THE UPR 30S AROUND 40 FROM THE
CHAMPLAIN VALLEY WWD.
TRAILING FRONTAL BOUNDARY AND INCREASING SWLY FLOW ALOFT RESULT IN
CONTINUED MILD WEATHER ON THURSDAY. WAVE LOW TRACKING NEWD ALONG THE
BNDRY THURSDAY AFTERNOON WILL BRING ANOTHER ROUND OF LIGHT RAINFALL
TO THE REGION...PERHAPS ENDING AS SNOW SHOWERS THURSDAY NIGHT AS
BOUNDARY SHIFTS SEWD AS A COLD FRONT ONCE LOW PASSES BY. IT APPEARS
HIGH TEMPERATURES WILL REACH THE UPR 40S TO NEAR 50 ON THURSDAY.
WHILE QPF IS NOT EXPECTED TO BE SIGNIFICANT WITH THE MID-WEEK
FRONTAL SYSTEM...THE 36-48 HR OF ABOVE FREEZING TEMPERATURES MAY
RESULT IN SOME ICE MOVEMENT ON OUR SOUTHERN RIVERS...AND THAT WILL
NEED TO BE MONITORED.
LOW-LEVEL NWLY FLOW AND STRONG CAA FRIDAY WILL RESULT IN HIGH TEMPS
BACK DOWN INTO THE LOW-MID 30S (ABOUT 10DEG BELOW CLIMO AVERAGE).
SOME MTN SNOW SHOWER ACTIVITY IS POSSIBLE THROUGH THE DAY FRIDAY.
GENERALLY DRY AND SEASONABLY COLD ON SATURDAY WITH HIGH PRESSURE
BUILDING IN FROM THE WEST. HIGH TEMPERATURES ON SATURDAY WILL REMAIN
IN THE MID 30S FOR MOST LOCATIONS.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
THROUGH 00Z TUESDAY...SCT/BKN VFR CIGS EXPECTED THROUGH
12Z...TRENDING SCT/SKC THEREAFTER AS MODESTLY GUSTY WEST TO
NORTHWESTERLY FLOW TO 25 KTS PERSISTS ACROSS THE AREA. SCT
FLURRIES POSSIBLE, MAINLY AT KMSS/KSLK TERMINALS WITH BRIEF VSBY
RESTRICTIONS TO MVFR AT KSLK POSSIBLE THROUGH 06Z.
OUTLOOK 00Z TUESDAY THROUGH FRIDAY...
00Z TUESDAY THROUGH 18Z WEDNESDAY...VFR/HIGH PRESSURE/LIGHT
WINDS.
18Z WEDNESDAY THROUGH FRIDAY...WARM FRONT AND LOW PRESSURE BRING
POTENTIAL FOR SCATTERED RAIN SHOWERS WEDNESDAY AFTERNOON AND
EVENING...AND AGAIN LATE THURSDAY INTO THURSDAY NIGHT. PERIODS OF
MVFR/BRIEF IFR POSSIBLE WITH HIR TRRN OBSCD. PRECIPITATION MAY END
AS SNOW SHOWERS WITH A COLD FRONTAL PASSAGE ON FRIDAY.
&&
.CLIMATE...
--MIN TEMP RECORDS FOR 3/23--
BURLINGTON 1 SET IN 1934
MONTPELIER -1 SET IN 2004
MT. MANSFIELD -8 SET IN 1959
MASSENA -2 SET IN 2014
--LOW MAX RECORDS FOR 3/23--
BURLINGTON 16 SET IN 1934
MONTPELIER 21 SET IN 1997
ST. JOHNSBURY 20 SET IN 1934
MT. MANSFIELD 10 SET IN 1997
MASSENA 21 SET IN 1983
&&
.EQUIPMENT...
AS OF 337 PM EDT SUNDAY...KTYX DOPPLER RADAR IS INOPERABLE UNTIL
FURTHER NOTICE. ELECTRONICS TECHNICIANS HAVE ASSESSED THAT IT`S A
MAJOR REPAIR...AND PARTS ARE NOW NOT EXPECTED UNTIL SOMETIME
MONDAY OR TUESDAY. THE INSTALLATION WILL REQUIRE LIKELY A FULL DAY
SO THE DOWNTIME IS EXPECTED TO STRETCH AT LEAST INTO TUESDAY. WE
APOLOGIZE FOR THE ABSENCE OF RADAR DATA FROM THE SITE WHILE PARTS
ARE AWAITED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WIND CHILL ADVISORY FROM 5 AM TO 11 AM EDT MONDAY FOR VTZ003-
004-006-007-016.
NY...WIND CHILL ADVISORY FROM 5 AM TO 11 AM EDT MONDAY FOR
NYZ029>031-034.
&&
$$
SYNOPSIS...NASH
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...BANACOS
AVIATION...JMG
CLIMATE...WFO BTV
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
441 AM EDT SAT MAR 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE AREA TODAY. LOW PRESSURE WILL
PASS SOUTHEAST OF THE REGION LATE SUNDAY INTO TUESDAY. HIGH
PRESSURE WILL BUILD OVER THE AREA WEDNESDAY. A COLD FRONT WILL
APPROACH THE AREA ON THURSDAY STALLING JUST OF THE REGION THURSDAY
NIGHT. LOW PRESSURE WILL MOVE ALONG THIS FRONT FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 4 AM SATURDAY...THE LATEST SURFACE ANALYSIS SHOWS THE 1008
MB LOW PRESSURE SYSTEM APPROX 225 MILES EAST OF OCEAN CITY, MD
WITH A 1020 MB HIGH CENTERED OVER MD. THE LOW WILL CONTINUE TO
LIFT NE TODAY WITH THE HIGH MIGRATING SOUTH ACROSS THE AREA
THROUGH THE DAY AND SETTLING OFFSHORE LATE THIS AFTERNOON AND
EVENING, ALLOWING LIGHT N WINDS TO BACK TO W THIS AFTERNOON THEN
SW LATE TODAY. STRATUS CONTINUES TO ADVECT SOUTH ACROSS THE AREA
EARLY THIS MORNING WITH ONLY SWRN PORTIONS OF ONSLOW AND DUPLIN
COUNTIES CLEAR, HOWEVER EXPECT THESE AREAS TO BECOME CLOUDY OVER
THE NEXT HOUR TO SO. THE STRATUS WILL LIKELY LINGER MID TO LATE
MORNING BEFORE ERODING AND THE HRRR EVEN HOLDS ON TO IT ACROSS THE
COASTAL PLAIN UNTIL EARLY AFTERNOON, THEN SUNNY TO PARTLY CLOUDY
SKIES EXPECTED TO DEVELOP THIS AFTERNOON. TEMPS WILL LIKELY HOLD
IN THE 40S TO LOWER 50S THIS MORNING WITH CLOUD COVER, BUT ONCE
THE LOW CLOUDS ERODE EXPECT TEMPS TO WARM INTO THE MID 60S INLAND
WHILE HIGHS IN THE LOW TO MID 50S CAN BE EXPECTED ACROSS THE
NORTHERN BEACHES AND UPPER 50S TO AROUND 60S SOUTHERN BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
AS OF 4 AM SATURDAY...SFC HIGH PRES OFFSHORE DISSIPATES TONIGHT
WITH A BACKDOOR COLD FRONT PUSHING SOUTH ACROSS THE MID ATLANTIC
STATES. THE FRONT IS EXPECTED TO BE JUST SOUTH OF THE VA/NC
BORDER AROUND 12Z SUNDAY. EXPECT MAINLY CLEAR SKIES THROUGH THE
EVENING HOURS BUT INCREASING MID AND HIGH CLOUDS EXPECTED AFTER
MIDNIGHT AS SOUTHERN STREAM MOISTURE LIFTS NORTH ACROSS THE GULF
STATES AND SOUTHEAST. LIGHT SW WINDS CONTINUE THROUGH THE
OVERNIGHT WITH LOWS A FEW DEGREES WARMER THAN TODAY, MAINLY IN THE
MID 40S. HYDROLAPSE RATES SUPPORT FOG DEVELOPMENT TONIGHT HOWEVER
CROSSOVER TEMPS ARE NOT EXPECTED TO BE REACHED AND GUIDANCE IS NOT
DEVELOPING FOG SO WILL NOT PUT IN THE FORECAST AT THIS TIME.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 355 AM SATURDAY...EARLY IN THE PERIOD THE UPPER LOW
VICINITY OF BAJA MEXICO WILL MOVE EASTWARD AS AN OPEN WAVE
DAMPENING IN THE CONFLUENT FLOW OVER THE EASTERN US. THIS SYSTEM
WILL PRODUCE CYCLOGENESIS ALONG A WAVY STALLED FRONT SOUTH OF THE
REGION. A SERIES OF BROAD LOW PRESSURE AREAS ARE FORECAST TO PASS
SOUTH OF THE REGION THROUGH MONDAY NIGHT. MAIN QUESTION IS
PLACEMENT AND AMOUNTS OF PRECIPITATION ASSOCIATED WITH THIS
SYSTEM. THE GFS HAS TRENDED WETTER AND NOW ALL THE OPERATIONAL
MODELS ARE INDICATING RAIN ACROSS PORTIONS OF EASTERN NC SUNDAY
THROUGH MONDAY ALTHOUGH THERE ARE SIGNIFICANT DIFFERENCES AMONG THEM.
THE GUIDANCE IS INDICATING THE POTENTIAL FOR A SHARP MOISTURE
GRADIENT ACROSS EASTERN NC AS HIGH PRESSURE TO THE NORTH INHIBITS
PRECIPITATION DEVELOPMENT ACROSS THE NORTHERN ZONES. CONSENSUS OF
THE GUIDANCE SUGGESTS BEST PRECIPITATION POTENTIAL SOUTH OF
HIGHWAY 64 WITH ONLY LIGHT AMOUNTS EXPECTED TO THE NORTH. THE
HEAVIEST RAINS SHOULD OCCUR ALONG AND SOUTH OF HIGHWAY 70. THINK
LIGHT RAIN DEVELOPS SOMETIME SUNDAY AFTERNOON AND THEN BECOMES A
LITTLE MORE WIDESPREAD SUNDAY NIGHT AND MONDAY AS THE REGION
COMES UNDER THE INFLUENCE OF THE LEFT FRONT QUAD OF THE UPPER JET.
WAS TEMPTED TO RAISE POPS SOUTHERN AREAS TO LIKELY BUT THINK ITS
WORTH WAITING 1 MORE MODEL RUN TO SEE IF THE MODELS NARROW THE GAP
BETWEEN THEM. THE PRECIPITATION IS EXPECTED TO COME TO AN END
MONDAY NIGHT AS HIGH PRESSURE BUILDS OVER THE AREA FROM THE NORTH.
HIGH TEMPERATURES TRICKY FOR SUNDAY AS CLOUDS/NORTHERLY FLOW AND
POSSIBLE PRECIPITATION WILL LIMIT WARMING BUT STILL THINK LOWER TO
MIDDLE 60S A GOOD BET ACROSS MOST OF THE AREA AWAY FROM COLDER
NEAR SHORE WATERS. TEMPERATURES SUNDAY COULD DROP INTO THE UPPER
30S IN STRENGTHENING NORTHERLY FLOW WHICH CONTINUES MONDAY WITH
CLOUDY SKIES/PRECIPITATION PRODUCING BELOW NORMAL HIGHS IN THE
LOWER 50S.
SHOULD HAVE A COUPLE OF DRY DAYS TUESDAY AND WEDNESDAY AS HIGH
PRESSURE BUILDS OVER THE AREA. HIGHS TUESDAY WILL CONTINUE BELOW
NORMAL IN THE MID TO UPPER 50S MOST AREAS WITH MODERATING
SOUTHERLY FLOW PRODUCING WARMER MID TO UPPER 60S AWAY FROM THE
BEACHES.
THERE ARE STILL DIFFERENCES FOR LATE IN THE WEEK AS A STRONG COLD
FRONT MOVES ACROSS THE EASTERN US BUT IT APPEARS THE COLD FRONT
WILL CROSS THE AREA THURSDAY NIGHT STALLING JUST TO THE SOUTH.
THEN FRIDAY A WAVE OF LOW PRESSURE WILL DEVELOP AND MOVE EAST
ALONG THE FRONT. RESULT OF THIS WILL BE THE POTENTIAL FOR
UNSETTLED WEATHER THURSDAY AND FRIDAY. HIGHS ON THURSDAY SHOULD BE
ABLE TO WARM WELL INTO THE 70S WITH COOLER TEMPS IN THE 60S
FRIDAY. HIGHS COULD BE EVEN LOWER DEPENDING ON HOW MUCH COLD AIR
CAN FILTER IN BEHIND THE FRONT.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 210 PM FRI...AN AREA OF STRATUS IS ADVECTING SOUTH ACROSS
THE AREA AND HAS REACHED THE HIGHWAY 70 CORRIDOR AFFECTING ALL TAF
SITES BUT OAJ TO THIS POINT, HOWEVER EXPECT IT TO REACH OAJ IN THE
NEXT HOUR OR TWO. VSBYS HAVE REMAINED GOOD BUT CIGS HAVE BEEN
GENERALLY AROUND 1-1.5K FT, OCCASIONALLY DROPPING JUST BELOW INTO
THE IFR RANGE.
HIGH CONFIDENCE THAT MVFR CIGS WILL PREVAIL AT THE TERMINALS EARLY
THIS MORNING BUT HAVE BELOW NORMAL CONFIDENCE FOR POTENTIAL IFR
CONDITIONS AS GUIDANCE NOT IN BEST AGREEMENT WITH AREAL EXTENT
AND HEIGHT OF THE STRATUS. NAM MOS IS UNDERDONE WITH THE STRATUS
WHILE THE GFS MOS APPEARS TOO PESSIMISTIC WITH IFR/LIFR ALREADY
IN PLACE WHERE CONDITIONS REMAIN MVFR. GENERALLY FOLLOWED UPSTREAM
TRENDS ALONG WITH THE GFS LAMP WHICH DOES BRING A PERIOD OF IFR TO
PGV AND ISO DURING THE PRE-DAWN HOURS AND KEEPS EWN AT MVFR. DID
BRING MVFR CIGS TO OAJ LOOKING AT TRENDS DESPITE MOST GUIDANCE
KEEPING CONDITIONS VFR FOR THE MOST PART. THE HRRR HOLDS ON TO THE
STRATUS MUCH LONGER THIS MORNING WHILE MOS GUIDANCE APPEARS TO
ERODE IT AROUND 12Z, WHICH IS LIKELY TOO QUICK AND HELD ONTO MVFR
CONDITIONS UNTIL 14-15Z, HOWEVER HRRR IS EVEN LATER THAN THIS,
ESPECIALLY ACROSS THE COASTAL PLAIN.
EXPECT LIGHT NORTHERLY WINDS THIS MORNING, BACKING TO SOUTHWEST
THIS AFTERNOON AND EVENING AS HIGH PRES SLIDES SOUTH ACROSS THE
AREA. PREDOMINANTLY VFR CONDITIONS EXPECTED THIS AFTERNOON AND
EVENING. FOG IS QUESTIONABLE TONIGHT. HYDROLAPSE RATES ARE
FAVORABLE FOR FOG DEVELOPMENT HOWEVER CROSSOVER TEMPS ARE NOT
EXPECTED TO BE REACHED AND MOS GUIDANCE KEEPING VFR CONDITIONS,
THEREFORE WILL NOT ADD FOG TO THE FORECAST AT THIS TIME.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM SATURDAY...VFR CONDITIONS SHOULD CONTINUE INTO
SUNDAY AFTERNOON AS HIGH PRES BUILDS INTO THE AREA. A SERIES OF
WEAK LOWS DEVELOP TO THE S SUNDAY AND SLOWLY LIFT NE MON. STILL
UNCERTAINTY WITH HOW MUCH MOISTURE WILL STREAM NORTH INTO EASTERN
NC BUT THERE WILL BE A POTENTIAL FOR MVFR CONDITIONS...ESPECIALLY
SRN TAF SITES SUNDAY EVENING THRU MON EVE. DRIER WEATHER AND
PREVAILING VFR CONDITIONS ARE EXPECTED FOR TUESDAY AND WEDNESDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 430 AM SATURDAY...N WINDS CONTINUE AROUND 10-20 KT WITH
HIGHER GUSTS OFF THE OBX THIS MORNING BUT WILL BE DIMINISHING
THROUGH THE DAY AND HIGH PRES MIGRATES SOUTH ACROSS THE AREA
TODAY. VARIABLE WINDS LESS THAN 10 KT EXPECTED THIS AFTERNOON,
BECOMING SW THIS EVENING AND INCREASING UP TO 15 KT LATE TONIGHT
AHEAD OF A BACKDOOR COLD FRONT, WHICH IS PROGGED TO BE JUST NORTH
OF THE WATERS AT 12Z SUNDAY. CONTINUE TO FOLLOW NWPS CLOSELY FOR
SEAS WITH A LACK OF BUOY OBS ACROSS THE CWA BUT IT APPEARS TO BE
HANDLING CONDITIONS A BUOYS NORTH AND SOUTH OF THE REGION WELL.
WILL CONTINUE SCA NORTH OF OCRACOKE INLET THROUGH 11 AM FOR SEAS
AROUND 4-7 FT. SEAS EXPECTED TO SUBSIDE TO 3-5 FT THIS AFTERNOON
AND 2-4 FT TONIGHT. THE SOUTHERN WATERS WILL SEE 3-5 FT SEAS THIS
MORNING, SUBSIDING TO 2-3 FT THIS AFTERNOON AND TONIGHT.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM SATURDAY...MARINERS CAN EXPECT ROUGH CONDITIONS
SUNDAY NIGHT INTO TUESDAY. LIGHT WINDS EARLY SUNDAY WITH HIGH
PRESSURE OVER THE AREA WILL INCREASE OUT OF THE NORTH TO 15 TO 20
KT IN THE AFTERNOON. DEVELOPING LOW PRESSURE MOVING TO THE SOUTH
SUNDAY NIGHT AND MONDAY WILL TIGHTEN THE GRADIENT STRENGTHENING
THE NORTH TO NORTHEAST FLOW TO 20 TO 30 KT LATE SUNDAY NIGHT
THROUGH MONDAY EVENING. THERE IS POTENTIAL FOR A LOW END GALE
DURING THIS PERIOD OVER THE SOUTHERN AND CENTRAL WATERS. SEAS WILL
BUILD TO 7 TO 9 FT. WINDS WILL GRADUALLY DIMINISH LATE MONDAY
NIGHT TO 15 TO 25 KT AND 10 TO 20 KT TUESDAY WITH SEAS EXPECTED TO
DIMINISH BELOW 6 FT BY EVENING. VEERING WINDS FROM NE TO SE 10 TO
15 KT ARE EXPECTED ON WEDNESDAY AS HIGH PRESSURE TO THE NORTH
MOVES OFFSHORE. SEAS ARE FORECAST TO BE IN THE 2-4 FT RANGE.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ150-
152-154.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK
SHORT TERM...SK
LONG TERM...JME
AVIATION...JME/SK
MARINE...JME/SK
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
250 AM EDT SAT MAR 21 2015
.SYNOPSIS...
LOW PRESSURE WILL CONTINUE TO MOVE NORTHEAST AWAY FROM THE NORTH
CAROLINA COAST OVERNIGHT. HIGH PRESSURE WILL BUILD IN SATURDAY.
ANOTHER LOW PRESSURE WILL PASS SOUTHEAST OF THE REGION LATE SUNDAY
INTO TUESDAY. HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY. A
COLD FRONT WILL APPROACH THE AREA ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 2 AM SATURDAY...AREA OF STRATUS IS ADVECTING SOUTH ACROSS
THE AREA EARLY THIS MORNING AND HAS REACHED THE HIGHWAY 70
CORRIDOR AS OF 2 AM. EXPECT IT TO PUSH INTO SOUTHERN AREAS OVER
THE NEXT FEW HOURS. FOR THE MOST PART GUIDANCE IS KEEPING
VISIBILITIES 6 MILES OR GREATER AND UPSTREAM OBS ALL REPORTING
GOOD VISIBILITIES THEREFORE HAVE REMOVED FOG FROM THE FORECAST
BUT DID BUMP UP SKY COVER TO ACCOUNT FOR THE STRATUS.
THE LATEST SURFACE ANALYSIS SHOWS THE 1007 MB LOW PRESSURE SYSTEM
APPROX 200 MILES EAST OF OCEAN CITY, MD AND WILL CONTINUE TO LIFT
NE OVERNIGHT. DRY AIRMASS WILL SLOWLY BUILD IN FROM THE WEST
OVERNIGHT...WHILE A STRONG NORTHERN STREAM SHORTWAVE CROSSES WELL
NORTH OF THE REGION...WITH A WEAK SHORTWAVE TROUGH CROSSING LATER
LATE TONIGHT THOUGH WITH LITTLE IMPACT ON SENSIBLE WX.
FORECAST TEMPS HAVE BEEN ON TRACK AND EXPECT LOWS OVERNIGHT MAINLY
IN THE LOW 40S INLAND COUNTIES BUT COULD SEE A FEW UPPER 30S,
WHILE COASTAL SECTIONS WILL SEE LOWS IN THE LOW/MID 40S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
AS OF 315 PM FRIDAY...HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST SATURDAY WITH LIGHT AND VARIABLE WINDS THROUGHOUT THE
DAY. FLOW ALOFT WILL REMAIN WEST-NORTHWESTERLY. PWATS DROP TO
LESS THAN ONE HALF INCH WITH FORECAST SOUNDINGS INDICATING VERY
DRY MID/LOW LEVELS. TEMPS SATURDAY WILL BUILD INTO THE LOW TO MID
60S ACROSS INLAND LOCATIONS WITH MID/UPPER 50S EXPECTED ALONG AREA
BEACHES.
&&
.LONG TERM /TONIGHT THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...A SERIES OF WEAK SFC LOWS WILL MOVE THROUGH
THE GULF COAST REGION DURING THE LATTER HALF OF THE WEEKEND INTO
EARLY NEXT WEEK. THERE ARE STILL DIFFERENCES IN THE GUIDANCE WITH
HOW MUCH IF ANY PRECIPITATION MAKES IT NORTH INTO EASTERN NC WITH
THESE SYSTEMS. WILL CONT FORECAST OF 20-30% POPS SUNDAY AND 30-40%
MONDAY HIGHEST BOTH DAYS SOUTHERN ZONES. TEMPERATURES WILL BE NEAR
NORMAL SUNDAY WITH UPR 50S OBX TO MID 60S INLAND AREAS AND BELOW
NORMAL MONDAY WITH HIGHS IN THE LWR TO MID 50S.
THE INITIAL SOUTHERN STREAM SYSTEM MOVES OFF THE SE COAST LATE
MONDAY WITH A TRAILING NORTHERN STREAM TROF CROSSING THE AREA LATE
MONDAY NIGHT OR EARLY TUESDAY. WILL MAINTAIN SLIGHT CHANCE POPS
ALONG THE COAST MONDAY NIGHT FOR THE SECONDARY UPPER TROF BUT
SYSTEM WILL LACK AMS MSTR AND LIKELY MANY AREAS WILL RMN DRY.
TEMPS WILL CONT BELOW NORMAL ON TUE WITH HIGHS IN THE 50S.
HIGH PRESSURE WILL BUILD ACRS THE AREA THROUGH MIDWEEK WITH TEMPS
RETURNING TO NEAR NORMAL WEDNESDAY...MAINLY 60S FOR HIGHS...THEN
ABOVE NORMAL THURSDAY WITH HIGH TEMPS REACHING THE MID 70S ACRS
INLAND AREAS. WILL CONT FORECAST OF CHANCE POPS FOR BOTH THU AND
FRI UNTIL MODELS CAN COME INTO BETTER TIMING AGREEMENT OF THE COLD
FRONT. BELOW NORMAL TEMPS EXPECTED BEHIND THE FRONT FOR NEXT
WEEKEND.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SATURDAY/...
AS OF 210 PM FRI...AN AREA OF STRATUS IS ADVECTING SOUTH ACROSS
THE AREA AND HAS REACHED THE HIGHWAY 70 CORRIDOR AFFECTING ALL TAF
SITES BUT OAJ TO THIS POINT, HOWEVER EXPECT IT TO REACH OAJ IN THE
NEXT HOUR OR TWO. VSBYS HAVE REMAINED GOOD BUT CIGS HAVE BEEN
GENERALLY AROUND 1-1.5K FT, OCCASIONALLY DROPPING JUST BELOW INTO
THE IFR RANGE.
HIGH CONFIDENCE THAT MVFR CIGS WILL PREVAIL AT THE TERMINALS EARLY
THIS MORNING BUT HAVE BELOW NORMAL CONFIDENCE FOR POTENTIAL IFR
CONDITIONS AS GUIDANCE NOT IN BEST AGREEMENT WITH AREAL EXTENT
AND HEIGHT OF THE STRATUS. NAM MOS IS UNDERDONE WITH THE STRATUS
WHILE THE GFS MOS APPEARS TOO PESSIMISTIC WITH IFR/LIFR ALREADY
IN PLACE WHERE CONDITIONS REMAIN MVFR. GENERALLY FOLLOWED UPSTREAM
TRENDS ALONG WITH THE GFS LAMP WHICH DOES BRING A PERIOD OF IFR TO
PGV AND ISO DURING THE PRE-DAWN HOURS AND KEEPS EWN AT MVFR. DID
BRING MVFR CIGS TO OAJ LOOKING AT TRENDS DESPITE MOST GUIDANCE
KEEPING CONDITIONS VFR FOR THE MOST PART. THE HRRR HOLDS ON TO THE
STRATUS MUCH LONGER THIS MORNING WHILE MOS GUIDANCE APPEARS TO
ERODE IT AROUND 12Z, WHICH IS LIKELY TOO QUICK AND HELD ONTO MVFR
CONDITIONS UNTIL 14-15Z, HOWEVER HRRR IS EVEN LATER THAN THIS,
ESPECIALLY ACROSS THE COASTAL PLAIN.
EXPECT LIGHT NORTHERLY WINDS THIS MORNING, BACKING TO SOUTHWEST
THIS AFTERNOON AND EVENING AS HIGH PRES SLIDES SOUTH ACROSS THE
AREA. PREDOMINANTLY VFR CONDITIONS EXPECTED THIS AFTERNOON AND
EVENING. FOG IS QUESTIONABLE TONIGHT. HYDROLAPSE RATES ARE
FAVORABLE FOR FOG DEVELOPMENT HOWEVER CROSSOVER TEMPS ARE NOT
EXPECTED TO BE REACHED AND MOS GUIDANCE KEEPING VFR CONDITIONS,
THEREFORE WILL NOT ADD FOG TO THE FORECAST AT THIS TIME.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...VFR CONDITIONS SHOULD DOMINATE THRU SAT NIGHT
AS HIGH PRES BUILDS INTO THE AREA WITH DRIER AIR OVERSPREADING
REGION. A SERIES OF WEAK LOWS DEVELOP TO THE S SUNDAY AND SLOWLY
LIFT NE MON. STILL UNCERTAINTY WITH HOW MUCH MOISTURE WILL STREAM
NORTH INTO EASTERN NC BUT THERE WILL BE A POTENTIAL FOR MVFR
CONDITIONS...ESPECIALLY SRN TIER THRU MON EVE.
&&
.MARINE...
SHORT TERM /THROUGH SATURDAY/...
AS OF 1020 PM FRIDAY...NO UPDATED NEEDED...CURRENT FORECAST IN
GOOD SHAPE. LATEST OBS SHOW NW WINDS 10-20KT AND SEAS 4-7FT NORTH
OF OCRACOKE AND 3-5FT SOUTH. SFC ANALYSIS CONTINUES TO SHOW THE
LOW PRESSURE SYS OFF THE DELMARVA COAST...AND WILL CONTINUE TO
LIFT NE AWAY FROM NC OVERNIGHT. COULD SEE GUSTS TO 25KT FOR THE
CENTRAL AND NORTHERN WATERS LATE TONIGHT AS LOW LIFTS NE. SEAS
WILL CONTINUE TO GRADUALLY SUBSIDE LATE TONIGHT INTO SATURDAY AS
HIGH PRESSURE BUILDS OVER THE WATERS FROM THE NORTHWEST. WINDS
REMAIN NORTHERLY EARLY SATURDAY THEN BACK WEST LATER IN THE DAY,
AND GENERALLY BELOW 15 KNOTS. SEAS SUBSIDE 2 TO 4 FT BY SATURDAY
AFTERNOON. SCA REMAINS IN EFFECT THROUGH LATE SAT MORNING NORTH OF
OCRACOKE.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...LIGHT WINDS EXPECTED SAT NIGHT INTO EARLY
SUNDAY WITH HIGH PRESSURE OVER THE AREA. AS A SERIES OF LOWS
DEVELOP TO THE S LATE SUNDAY AND MONDAY. NNE WINDS 10 TO 15 KTS
EXPECTED LATE SUNDAY AND INCREASING TO 15 TO 25 KTS SUNDAY NIGHT
AND MON. SEAS OF 3 TO 4 FT SUN EVENING WILL BUILD TO 6 TO 7 FT
MON. MODERATE NNE WINDS WILL MAINTAIN ELEVATED SEAS INTO TUESDAY
WITH NE FLOW FORECAST TO DIMINISH TO 10 TO 15 KT LATE. NE-E WINDS
DMNSH FURTHER TUE NIGHT INTO WED TO 10 KT OR LESS WITH SEAS
SUBSIDING TO 2 TO 4 FEET.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ150-
152-154.
&&
$$
SYNOPSIS...DAG
NEAR TERM...SK/BM
SHORT TERM...DAG
LONG TERM...JAC
AVIATION...JAC/SK
MARINE...JAC/CQD/DAG/BM
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1241 PM CDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1241 PM CDT SAT MAR 21 2015
RADAR RETURNS CONTINUE OVER THE WESTERN COUNTIES BUT LITTLE IS
REACHING THE GROUND. THE RAP AND HRRR HAVE ONLY A VERY LITTLE QPF
ENTERING BENSON COUNTY BUT THE HOPWRF CONTINUES TO SHOW A NARROW
BAND OF ACCUMULATING SNOW REACHING AS FAR EAST AS DEVILS LAKE.
GIVEN THE LOW DEW POINTS AND LACK OF ANYTHING SIGNIFICANT SO
FAR...BACKED OFF A BIT ON POPS BUT KEPT A MENTION OF SNOW GOING
THROUGH THE REST OF THE DAY OVER THE WESTERN CWA. IT WILL BE A
POP BUT LOW QPF SITUATION AT LEAST AS IT APPEARS AT THIS TIME.
UPDATE ISSUED AT 954 AM CDT SAT MAR 21 2015
DESPITE A FAIR AMOUNT OF RADAR RETURNS OVER OUR WESTERN COUNTIES
WEB CAMS AND SFC OBS HAVE BEEN SLOW TO SHOW MUCH REACHING THE
SFC...WHICH MAKES SENSE GIVEN THE DRYNESS OF THE LOWER LAYERS OF
THE ATMOSPHERE. HOWEVER...LEEDS WEB CAMS HAVE SHOWN SOME SIGNS OF
FLAKES...AND THE SHORT RANGE MODELS ARE IN DECENT AGREEMENT ON
BRINGING A NARROW BAND INTO OUR WESTERN COUNTIES. WILL CONTINUE TO
KEEP HIGH POPS IN THE DEVILS LAKE BASIN THROUGH THE REST OF THE
MORNING INTO THE AFTERNOON...BUT WILL KEEP AMOUNTS BELOW AN INCH
UNLESS THERE ARE SIGNS OF BANDING SETTING UP IN THE NEXT FEW
HOURS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 350 AM CDT SAT MAR 21 2015
MODELS IN DECENT AGREEMENT AND WILL USE A BLEND FOR THIS FORECAST.
THE MAIN CHALLENGE WILL BE SNOW CHANCES AND AMOUNTS. SFC RIDGING
WILL BE IN PLACE ACROSS THE REGION WITH A COUPLE WEAK WAVES
INDUCING FRONTOGENESIS AND BANDS OF SNOW. THESE SNOW BANDS WILL
LIKELY BE STRONGEST TO THE WEST...AND WEAKEN AS THEY ENTER THE
DRIER AIRMASS TO THE EAST.
TODAY...THE DEVILS LAKE BASIN AND POTENTIALLY AREAS AROUND WILL
LIKELY RECEIVE SNOWFALL. WENT WITH A HIGH POP/LOW QPF IDEA WITH UP
TO AN INCH OF SNOW. SYNOPTIC SUPPORT IS WEAK SO FEEL FAIRLY
CONFIDENT THAT MOST AREAS WILL REMAIN UNDER AN INCH OF SNOWFALL.
SUNDAY...SIMILAR SCENARIO ALTHOUGH THE RIDGING WILL BE SHIFTED
SLIGHTLY EAST AND SYNOPTIC SUPPORT IS SLIGHTLY STRONGER. CURRENT
SIGNALS INDICATE THIS BAND SETTING UP FROM THE DEVILS LAKE BASIN
INTO THE SOUTHERN VALLEY/WC MN...WITH 1-3 INCHES OF SNOW ACROSS
MOST OF THIS AREA. THE INDICATORS FOR BANDING POTENTIAL ARE
PRESENT ALBEIT WEAK...AND WITH PWATS NEAR 0.5 INCHES WOULD NOT BE
SURPRISED IF A NARROW BAND OF HIGHER AMOUNTS OCCUR (MOST LIKELY
ACROSS THE SOUTHERN FA GIVEN THE CURRENT MODEL SIGNALS).
SUNDAY NIGHT...GOOD AGREEMENT AMONG THE MODELS FOR A STRONGER
UPPER LEVEL WAVE PROPAGATING ALONG THE INTERNATIONAL BORDER
LEADING TO ACCUMULATING SNOWFALL.
TRENDED THE FORECAST TOWARD THE ABOVE IDEAS.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT SAT MAR 21 2015
MONDAY...RIDGING BETWEEN SYSTEMS SHOULD LEAD TO SOME SOLAR AND MAX
TEMPS INTO THE 40S MOST AREAS.
TUESDAY-FRIDAY...AN OPEN-WAVE UPPER-AIR TROUGH WILL SPIN UP A
SURFACE LOW PRESSURE SYSTEM THAT WILL START TO AFFECT THE WESTERN
PART OF THE FORECAST AREA WITH A RAIN/SNOW MIX ON TUESDAY. THE
TROUGH DEVELOPS INTO A CLOSED LOW AS IT MOVES EASTWARD WITH THE
SURFACE LOW STRENGTHENING ON WEDNESDAY AND PRECIPITATION FINALLY
EXITING THE AREA ON THURSDAY MORNING. A FAIR-WEATHER HIGH WILL
PREVAIL LATER ON THURSDAY THROUGH EARLY SATURDAY.
DAYTIME TEMPERATURES WILL BE IN THE THIRTIES TUESDAY THROUGH
THURSDAY AND THEN WARMING TO THE FORTIES AFTER THAT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1241 PM CDT SAT MAR 21 2015
BAND OF MID CLOUD WILL CONTINUE OVER THE KDVL-KGFK-KFAR AREA WHILE
WISPY CIRRUS PREVAIL EAST OF THE VALLEY. LIGHT SNOW HEADING TOWARD
DVL BASIN WEAKENING AS IT ENCOUNTERS DRIER AIR AND USED A -SHSN
CHARACTERIZATION FOR PCPN THERE THIS AFTERNOON. LIGHT WINDS FAVORING
NORTHEAST WILL INCREASE A BIT AND SHIFT TO THE EAST OVERNIGHT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/LUKES
AVIATION...WJB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
129 AM CDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 129 AM CDT SAT MAR 21 2015
INCREASING ISENTROPIC LIFT AND INCREASING DIVERGENT FLOW ALOFT IN
THE RIGHT ENTRANCE REGION OF AN UPPER JET STREAK RESULTING IN
INCREASING CLOUDS ACROSS WEST AND CENTRAL NORTH DAKOTA. LATEST
RADAR IMAGERY MORE IN LINE WITH THE 00Z GFS WITH THE MAIN BAND OF
OVERRUNNING PRECIPITATION ACROSS THE NORTH BUT SOME ACTIVITY AS
FAR SOUTH AS I94. THUS KEPT IN WHAT THE INHERITED FORECAST HAD
WITH SOME MINOR TWEAKS. WENT LIKELY POPS ACROSS THE NORTH WHERE WE
EXPECT SOME LIGHT ACCUMULATING SNOW THIS MORNING.
UPDATE ISSUED AT 933 PM CDT FRI MAR 20 2015
LATEST HRRR RUNS SUGGEST THE PRECIP WILL TREND NORTH OF THE BORDER
DURING THE OVERNIGHT HOURS AND DEVELOP SOUTH INTO NORTH CENTRAL
NORTH DAKOTA BEFORE SUNRISE. NEW NAM RUN SIMILAR BUT A BIT FURTHER
WEST. EITHER ONE IS WELL WITHIN THE CURRENT FORECAST ENVELOPE AND
WILL NOT MAKE ANY CHANGES TO POPS FOR THIS REASON. TEMPERATURES
AND WINDS LOOK GOOD.
UPDATE ISSUED AT 639 PM CDT FRI MAR 20 2015
STRATUS CONTINUES TO SLIDE SOUTH ACROSS THE REGION. THE STRATUS
REPRESENTS THE BAROCLINIC ZONE THAT WILL BE THE KEY IN LIFTING THE
FLOW OVER THE COOL AIR AND GENERATE SNOW ACROSS THE NORTH AND EAST.
MADE SOME ADJUSTMENTS FOR TEMPERATURES AND CLOUDS. OTHERWISE SO FAR
FORECAST TRENDING OK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 348 PM CDT FRI MAR 20 2015
CURRENT SURFACE ANALYSIS PLACES LOW SETTLING DOWN THROUGH EASTERN
SOUTH DAKOTA WITH COLD FRONT SETTLING THROUGH SOUTHEAST INTO WEST
CENTRAL NORTH DAKOTA. CLEAR SKIES AND VERY WARM TEMPS ARE NOTED
AHEAD OF THE FRONT...WITH LOW CLOUDS AND CHILLY TEMPS BEHIND.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...CLOUD COVER WILL
CONTINUE TO SPREAD ACROSS THE AREA THROUGH THE AFTERNOON AS COOL
AIRMASS SPREADS IN. SOME LIGHT SNOW MAY START DEVELOPING LATE
TONIGHT OVER THE NORTHWEST AND SPREAD TO THE SOUTHEAST AS RIGHT
ENTRANCE REGION OF UPPER JET SLIDES THROUGH THE REGION WHILE SOME
MODEST ISENTROPIC LIFT DEVELOPS.
ON SATURDAY...CHANCES FOR SNOW CONTINUE PRIMARILY OVER THE NORTHERN
PORTIONS OF THE AREA IN MODEST ISENTROPIC LIFT AS AFOREMENTIONED JET
SLOWLY WORKS ITS WAY OFF TO THE EAST. SNOW AMOUNTS SHOULD REMAIN
LIGHT...MAINLY UNDER AN INCH. TEMPERATURES WILL AGAIN BE WARMEST OFF
TO THE SOUTHWEST WHILE COLD AIRMASS REMAINS OVER THE NORTH CENTRAL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 348 PM CDT FRI MAR 20 2015
SEVERAL ROUNDS OF RAIN AND ACCUMULATING SNOW SATURDAY THROUGH
WEDNESDAY.
THERE IS THE POTENTIAL FOR WIDESPREAD ACCUMULATING SNOW SATURDAY
AFTERNOON THROUGH LATE SUNDAY NIGHT. ALL OF THE MAJOR OPERATIONAL
MODELS (GFS/ECMWF/GEM/NAM/SREF) CONTINUE TO INDICATE ACCUMULATING
SNOW NORTH AND EAST OF THE MISSOURI RIVER SATURDAY THROUGH SUNDAY.
A RATHER PRONOUNCED BAROCLINIC ZONE WILL BISECT NORTH DAKOTA.
NORTH AND EAST OF THE MISSOURI RIVER TEMPERATURES ARE EXPECTED TO
REMAIN NEAR OR BELOW FREEZING. WHILE TEMPERATURES SOUTH AND WEST
OF THE RIVER SHOULD CLIMB INTO THE 40S AND 50S. UPSLOPE
FLOW...LEE CYCLOGENESIS AND A FAVORABLE CURVED UPPER LEVEL
JET...SHOULD PRODUCE WIDESPREAD 2 TO 4 INCHES ACROSS THE NORTH
AND EAST.
THE NEXT SYSTEM COULD IMPACT THE REGION MONDAY NIGHT THROUGH
WEDNESDAY. THERE IS STILL A LOT OF UNCERTAINTY IN THE EXACT TRACK
OF THIS SYSTEM. OVER THE PAST TWO MODEL RUNS THE GFS HAS
COMPLETELY FLIP FLOPPED FROM A NORTHERN SOLUTION TO A SOUTHERN
SOLUTION. THE ECMWF REMAINS FAIRLY CONSISTENT WITH A MIDDLE OF THE
ROAD SOLUTION. THERE APPEARS TO BE A GREAT DEAL OF WARM AIR WRAPPED
UP AHEAD OF THIS SYSTEM. THEREFORE...INITIAL PRECIPITATION MAY BE
ALL RAIN BEFORE CHANGING OVER TO SNOW AS COLD AIR MOVES IN BEHIND
THE LOW. TEMPERATURES WILL VARY GREATLY BASED ON THE EXACT
TRACK OF THE LOW PRESSURE CENTER. THEREFORE...WHILE HEAVY
SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG
FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROWEL SET UP
ACROSS THE REGION...TOO MUCH UNCERTAINTY REMAINS TO NAIL DOWN
SPECIFIC LOCATIONS AND SNOWFALL AMOUNTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 129 AM CDT SAT MAR 21 2015
MVFR-IFR CONDITIONS ARE EXPECTED TO PREVAIL FROM KISN-KMOT-KDIK-
KBIS WHERE EASTERLY UPSLOPE FLOW WILL MAINTAIN A STRATUS DECK. KJMS
SHOULD REMAIN VFR THROUGH THE PERIOD. SNOW WILL DEVELOP ACROSS THE
NORTH...KISN-KMOT...WHERE SUB-IFR CONDITIONS ARE POSSIBLE. VLIFR-
LIFR AT KDIK WILL ALSO PERSIST UNTIL AROUND MID SATURDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JJS
LONG TERM...AJ
AVIATION...NH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1047 PM CDT SUN MAR 22 2015
.AVIATION...
LOW CLOUDS AND FOG ARE EXPECTED OVER MUCH OF THE WESTERN HALF OF
OKLAHOMA EARLY MONDAY. THE MVFR AND IFR SHOULD CLEAR BY 231700
FROM EAST TO WEST. GUSTY SOUTH WINDS WILL DEVELOP MONDAY
AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 930 PM CDT SUN MAR 22 2015/
DISCUSSION...
THERE IS SOME CONCERN THAT DENSE FOG MAY OCCUR TONIGHT. CLEAR
SKIES...RECENT RAIN...AND GENERALLY LIGHT WINDS ARGUE IN
FAVOR...BUT THE WIND MAY BE A LITTLE TOO STRONG...AND THE MOISTURE
TOO SHALLOW...FOR DENSE FOG. IN ANY CASE...SOME FOG REMAINS
LIKELY...AND THE EXISTING FORECAST LOOKS REASONABLE.
WE ARE ALSO IN THE PROCESS OF ISSUING A FIRE WEATHER WATCH FOR
TUESDAY...WITH THE USUAL COMBINATION OF WARMTH...DRYNESS...AND
WINDINESS.
ALL OTHER ASPECTS OF THE FORECAST ALSO LOOK GOOD AT THIS
TIME...AND NO OTHER CHANGES ARE PLANNED THIS EVENING...UNLESS
CONFIDENCE GROWS WITH RESPECT TO DENSE FOG OVERNIGHT.
PREV DISCUSSION... /ISSUED 600 PM CDT SUN MAR 22 2015/
AVIATION...
LOW CLOUDS AND FOG ARE EXPECTED OVER MUCH OF THE WESTERN HALF OF
OKLAHOMA EARLY MONDAY. THE MVFR AND IFR SHOULD CLEAR BY 231700
FROM EAST TO WEST. GUSTY SOUTH WINDS WILL DEVELOP MONDAY
AFTERNOON.
PREV DISCUSSION... /ISSUED 224 PM CDT SUN MAR 22 2015/
DISCUSSION...
LOW CLOUDS WILL CONTINUE TO ERODE THROUGH THE AFTERNOON ACROSS
SOUTHWEST OKLAHOMA AND NORTH TEXAS. NAM AND RAP SOUNDINGS SUGGEST
THAT FOG...SOME DENSE...WILL REFORM AGAIN TONIGHT...ESPECIALLY
ACROSS WEST CENTRAL...SOUTHWEST OKLAHOMA AND NORTH TEXAS.
ON MONDAY...AN ISOLATED STORM OR TWO MAY DEVELOP IN FAR WESTERN
OKLAHOMA NEAR A DRYLINE. BETTER CHANCES WILL REMAIN NORTH AND
EAST OF THIS AREA MONDAY NIGHT AND EARLY TUESDAY NORTH OF A WARM
FRONT IN KANSAS. EARLY TUESDAY...DRIER AIR WILL PUSH INTO WESTERN
PARTS OF OKLAHOMA AND NORTH TEXAS...AS A SHORTWAVE TROUGH MOVES
ACROSS THE CENTRAL PLAINS. BREEZY NORTHWEST TO WEST WINDS TUESDAY
AFTERNOON AND RATHER LOW HUMIDITY WILL INCREASE THE CHANCE OF
WILDFIRES.
FARTHER EAST...THUNDERSTORMS WILL BE POSSIBLE...MAINLY IN EASTERN
OKLAHOMA. MOISTURE WILL QUICKLY RETURN ON WEDNESDAY AHEAD OF
ANOTHER FRONT. STORM CHANCES WILL INCREASE BY WEDNESDAY
AFTERNOON...ESPECIALLY ALONG AND SOUTHEAST OF INTERSTATE 44.
INSTABILITY AND SHEAR WILL SUPPORT SEVERE STORMS...BUT FAVOR
LOWER DEWPOINT VALUES GFS/EC COMPARED WITH NAM12. HAIL...STRONG
WINDS AND HEAVY RAIN WILL BE THE IMPACTS WITH STORMS WEDNESDAY
AFTERNOON AND EVENING.
COOLER AND DRIER AIR WILL FILTER INTO THE SOUTHERN PLAINS THURSDAY
INTO FRIDAY. ANOTHER TROUGH WILL MOVE ACROSS THE AREA ON FRIDAY.
ASSOCIATED CLOUD COVER SHOULD KEEP TEMPERATURES FROM FALLING TO
OR BELOW FREEZING IN NORTHERN OKLAHOMA EARLY FRIDAY MORNING.
MANY AREAS HAVE BEEN ABOVE FREEZING FOR AN EXTENDED PERIOD. EARLY
SATURDAY MORNING...A FEW AREAS ACROSS THE NORTHERN HALF OF THE
STATE MAY SEE A LIGHT FREEZE.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 50 77 59 80 / 0 0 0 0
HOBART OK 49 80 54 81 / 0 0 0 0
WICHITA FALLS TX 49 81 58 84 / 0 0 0 0
GAGE OK 46 82 49 79 / 0 10 0 0
PONCA CITY OK 48 78 57 79 / 0 10 20 0
DURANT OK 47 74 55 79 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON FOR OKZ004-005-009>011-014>016-021-022-033>036.
TX...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON FOR TXZ083-084.
&&
$$
23/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
930 PM CDT SUN MAR 22 2015
.DISCUSSION...
THERE IS SOME CONCERN THAT DENSE FOG MAY OCCUR TONIGHT. CLEAR
SKIES...RECENT RAIN...AND GENERALLY LIGHT WINDS ARGUE IN
FAVOR...BUT THE WIND MAY BE A LITTLE TOO STRONG...AND THE MOISTURE
TOO SHALLOW...FOR DENSE FOG. IN ANY CASE...SOME FOG REMAINS
LIKELY...AND THE EXISTING FORECAST LOOKS REASONABLE.
WE ARE ALSO IN THE PROCESS OF ISSUING A FIRE WEATHER WATCH FOR
TUESDAY...WITH THE USUAL COMBINATION OF WARMTH...DRYNESS...AND
WINDINESS.
ALL OTHER ASPECTS OF THE FORECAST ALSO LOOK GOOD AT THIS
TIME...AND NO OTHER CHANGES ARE PLANNED THIS EVENING...UNLESS
CONFIDENCE GROWS WITH RESPECT TO DENSE FOG OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 600 PM CDT SUN MAR 22 2015/
AVIATION...
LOW CLOUDS AND FOG ARE EXPECTED OVER MUCH OF THE WESTERN HALF OF
OKLAHOMA EARLY MONDAY. THE MVFR AND IFR SHOULD CLEAR BY 231700
FROM EAST TO WEST. GUSTY SOUTH WINDS WILL DEVELOP MONDAY
AFTERNOON.
PREV DISCUSSION... /ISSUED 224 PM CDT SUN MAR 22 2015/
DISCUSSION...
LOW CLOUDS WILL CONTINUE TO ERODE THROUGH THE AFTERNOON ACROSS
SOUTHWEST OKLAHOMA AND NORTH TEXAS. NAM AND RAP SOUNDINGS SUGGEST
THAT FOG...SOME DENSE...WILL REFORM AGAIN TONIGHT...ESPECIALLY
ACROSS WEST CENTRAL...SOUTHWEST OKLAHOMA AND NORTH TEXAS.
ON MONDAY...AN ISOLATED STORM OR TWO MAY DEVELOP IN FAR WESTERN
OKLAHOMA NEAR A DRYLINE. BETTER CHANCES WILL REMAIN NORTH AND
EAST OF THIS AREA MONDAY NIGHT AND EARLY TUESDAY NORTH OF A WARM
FRONT IN KANSAS. EARLY TUESDAY...DRIER AIR WILL PUSH INTO WESTERN
PARTS OF OKLAHOMA AND NORTH TEXAS...AS A SHORTWAVE TROUGH MOVES
ACROSS THE CENTRAL PLAINS. BREEZY NORTHWEST TO WEST WINDS TUESDAY
AFTERNOON AND RATHER LOW HUMIDITY WILL INCREASE THE CHANCE OF
WILDFIRES.
FARTHER EAST...THUNDERSTORMS WILL BE POSSIBLE...MAINLY IN EASTERN
OKLAHOMA. MOISTURE WILL QUICKLY RETURN ON WEDNESDAY AHEAD OF
ANOTHER FRONT. STORM CHANCES WILL INCREASE BY WEDNESDAY
AFTERNOON...ESPECIALLY ALONG AND SOUTHEAST OF INTERSTATE 44.
INSTABILITY AND SHEAR WILL SUPPORT SEVERE STORMS...BUT FAVOR
LOWER DEWPOINT VALUES GFS/EC COMPARED WITH NAM12. HAIL...STRONG
WINDS AND HEAVY RAIN WILL BE THE IMPACTS WITH STORMS WEDNESDAY
AFTERNOON AND EVENING.
COOLER AND DRIER AIR WILL FILTER INTO THE SOUTHERN PLAINS THURSDAY
INTO FRIDAY. ANOTHER TROUGH WILL MOVE ACROSS THE AREA ON FRIDAY.
ASSOCIATED CLOUD COVER SHOULD KEEP TEMPERATURES FROM FALLING TO
OR BELOW FREEZING IN NORTHERN OKLAHOMA EARLY FRIDAY MORNING.
MANY AREAS HAVE BEEN ABOVE FREEZING FOR AN EXTENDED PERIOD. EARLY
SATURDAY MORNING...A FEW AREAS ACROSS THE NORTHERN HALF OF THE
STATE MAY SEE A LIGHT FREEZE.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 50 77 59 80 / 0 0 0 0
HOBART OK 49 80 54 81 / 0 0 0 0
WICHITA FALLS TX 49 81 58 84 / 0 0 0 0
GAGE OK 46 82 49 79 / 0 10 0 0
PONCA CITY OK 48 78 57 79 / 0 10 20 0
DURANT OK 47 74 55 79 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON FOR OKZ004-005-009>011-014>016-021-022-033>036.
TX...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON FOR TXZ083-084.
&&
$$
23/09
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1034 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FIRST VISUALS SHOW A WIDESPREAD LOW OVERCAST AND OBSERVATIONS
SHOW A LOT OF FOG IN THE 1-4 MILE RANGE. CLOUDS WILL BE MORE
COMMON THAN SUN TODAY AHEAD OF THE COLD FRONT THAT WILL ULTIMATELY
SHIFT OUR WINDS TO THE NW AND EVENTUALLY BRING SOME DRIER AIR AND
IMPROVEMENT.
I USED THE HRRR TO BUMP UP POPS INTO THE CENTRAL MOUNTAINS AS THE
GUIDANCE SUGGESTS SHOWERS WILL REMAIN FAIRLY ORGANIZED AS THEY
DROP OUT OF THE NRN MOUNTAINS...BEFORE BECOMING MORE SCATTERED
OVER THE SRN TIER COUNTIES.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACROSS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS REACHING
AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
LATEST TIMING SHOWS THE COLD MOVING THROUGH MY SOUTHERN ZONES BY
AROUND 00Z/8PM...AND PUSH SOUTH OF THE BORDER BY MIDNIGHT. SHOWERS
WILL DIMINISH RAPIDLY IN THE POST FRONTAL DRIER AIRMASS. OTHER
THAN SOME SCATTERED FLURRIES...IT WILL BE DRY OVER MOST OF THE
REGION BY LATE EVENING.
OVERNIGHT LOWS IN THE MID TEENS TO MID 20S WILL BE SOME 5 TO 10
DEG BELOW NORMAL FOR THE FIRST DAY OF SPRING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
WIDESPREAD LOW CIGS AND REDUCED VSBYS WILL GRADUALLY IMPROVE TODAY
AS A COLD FRONT SWEEPS SOUTHEAST ACROSS THE AIRSPACE FROM THE
GREAT LAKES. A BAND OF MAINLY LIGHT SHOWERS WILL ACCOMPANY THE
COLD FRONT THROUGH THE AIRSPACE LATER TODAY...WITH A RETURN TO VFR
PROJECTED FOR MOST SITES TONIGHT.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
757 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE THROUGH 13Z ACROSS THE
LAUREL HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT
DURING THE LATE MORNING AND AFTERNOON HOURS.
EXPECT NOTHING MORE THAN SOME VERY PATCHY/LIGHT DRIZZLE THROUGH
13Z.
TEMPS EARLY TODAY WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST
A DEG OR 2 IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME
PARTIAL CLEARING OCCURS.
ICY SPOTS ARE POSSIBLE ON UNTREATED ROADS.
WEAK RIDGE OF HIGH PRESSURE WILL SLIDE EAST OF THE REGION BY THE
LATE MORNING HOURS...ALLOWING AN 8-12 KT WSWRLY FLOW TO DEVELOP
BETWEEN IT...AND A STRONG COLD FRONT APPROACHING FROM THE GLAKES
REGION.
THE PERSISTENT AND MDTLY STG SUBSIDENCE INVERSION BASED BETWEEN
3-4 KFT AGL SHOULD HELP TO MAINTAIN PLENTY OF TRAPPED STRATUS AND
STRATO CU THIS MORNING. AFTERWARD...THE AFOREMENTIONED COLD FRONT
WILL SPARK SOME RAIN/SNOW SHOWERS ACROSS THE NW MTNS LATE THIS
MORNING AND THIS AFTERNOON. MUCH MORE ISOLATED-SCTD RAIN SHOWERS
WILL FALL ACROSS THE CENTRAL AND SOUTHERN PENN LATE THIS
AFTERNOON AND EARLY THIS EVENING.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACRS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS
REACHING AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE COLD FRONT SHOULD NEARLY BISECT THE STATE FROM NE-SW AT
00Z...AND PUSH ACROSS THE LOWER SUSQ VALLEY THIS EVENING.
GEFS AND 00Z-06 OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS
ACROSS THE NW MTNS ACCOMPANYING THE FROPA. EVEN THE LOWER SUSQ
VALLEY COULD SEE A SHOWER IN SPOTS WITH THE EARLY EVENING FROPA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
WIDESPREAD LOW CIGS AND REDUCED VSBYS WILL GRADUALLY IMPROVE TODAY
AS A COLD FRONT SWEEPS SOUTHEAST ACROSS THE AIRSPACE FROM THE
GREAT LAKES. RADAR SHOWS AN AREA OF -SN ALONG WARM FRONT THAT
WILL BRIEFLY AFFECT IPT THRU 13Z. A BAND OF -RA MAY ALSO ACCOMPANY
THE COLD FRONT THROUGH THE AIRSPACE LATER TODAY...WITH A RETURN
TO VFR PROJECTED FOR MOST SITES TONIGHT.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
527 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE THROUGH 13Z ACROSS THE
LAUREL HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT
DURING THE LATE MORNING AND AFTERNOON HOURS.
EXPECT NOTHING MORE THAN SOME VERY PATCHY/LIGHT DRIZZLE THROUGH
13Z.
TEMPS EARLY TODAY WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST
A DEG OR 2 IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME
PARTIAL CLEARING OCCURS.
ICY SPOTS ARE POSSIBLE ON UNTREATED ROADS.
WEAK RIDGE OF HIGH PRESSURE WILL SLIDE EAST OF THE REGION BY THE
LATE MORNING HOURS...ALLOWING AN 8-12 KT WSWRLY FLOW TO DEVELOP
BETWEEN IT...AND A STRONG COLD FRONT APPROACHING FROM THE GLAKES
REGION.
THE PERSISTENT AND MDTLY STG SUBSIDENCE INVERSION BASED BETWEEN
3-4 KFT AGL SHOULD HELP TO MAINTAIN PLENTY OF TRAPPED STRATUS AND
STRATO CU THIS MORNING. AFTERWARD...THE AFOREMENTIONED COLD FRONT
WILL SPARK SOME RAIN/SNOW SHOWERS ACROSS THE NW MTNS LATE THIS
MORNING AND THIS AFTERNOON. MUCH MORE ISOLATED-SCTD RAIN SHOWERS
WILL FALL ACROSS THE CENTRAL AND SOUTHERN PENN LATE THIS
AFTERNOON AND EARLY THIS EVENING.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACRS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS
REACHING AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE COLD FRONT SHOULD NEARLY BISECT THE STATE FROM NE-SW AT
00Z...AND PUSH ACROSS THE LOWER SUSQ VALLEY THIS EVENING.
GEFS AND 00Z-06 OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS
ACROSS THE NW MTNS ACCOMPANYING THE FROPA. EVEN THE LOWER SUSQ
VALLEY COULD SEE A SHOWER IN SPOTS WITH THE EARLY EVENING FROPA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
WIDESPREAD LOW CIGS AND REDUCED VSBYS CONTINUE TO IMPACT THE
AIRSPACE EARLY THIS MORNING. RADAR SHOWS AREA OF -RASN CROSSING
WRN NY AND SHOULD NOT AFFECT TAFS. UPDATED MDT/IPT WHICH DROPPED
INTO IFR CAT (CIGS). LNS OB NOT AVAILABLE IN SYSTEM BUT CALL DIAL
UP. LOOK FOR IMPROVING CONDS DURING THE DAYLIGHT HOURS AS WSW
WINDS BEGIN TO INCREASE AHEAD OF A COLD FRONT APPROACHING FROM THE
NW. THE FROPA WILL OCCUR FROM NW TO SE THIS AFTN-EVE AND MAY BE
ACCOMPANIED BY A BRIEF PD OF -RA. A RETURN TO VFR IS PROJECTED FOR
MOST SITES BY 00Z SUN.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
355 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE THROUGH 13Z ACROSS THE
LAUREL HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT
DURING THE LATE MORNING AND AFTERNOON HOURS.
EXPECT NOTHING MORE THAN SOME VERY PATCHY/LIGHT DRIZZLE THROUGH
13Z.
TEMPS EARLY TODAY WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST
A DEG OR 2 IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME
PARTIAL CLEARING OCCURS.
ICY SPOTS ARE POSSIBLE ON UNTREATED ROADS.
WEAK RIDGE OF HIGH PRESSURE WILL SLIDE EAST OF THE REGION BY THE
LATE MORNING HOURS...ALLOWING AN 8-12 KT WSWRLY FLOW TO DEVELOP
BETWEEN IT...AND A STRONG COLD FRONT APPROACHING FROM THE GLAKES
REGION.
THE PERSISTENT AND MDTLY STG SUBSIDENCE INVERSION BASED BETWEEN
3-4 KFT AGL SHOULD HELP TO MAINTAIN PLENTY OF TRAPPED STRATUS AND
STRATO CU THIS MORNING. AFTERWARD...THE AFOREMENTIONED COLD FRONT
WILL SPARK SOME RAIN/SNOW SHOWERS ACROSS THE NW MTNS LATE THIS
MORNING AND THIS AFTERNOON. MUCH MORE ISOLATED-SCTD RAIN SHOWERS
WILL FALL ACROSS THE CENTRAL AND SOUTHERN PENN LATE THIS
AFTERNOON AND EARLY THIS EVENING.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACRS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS
REACHING AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE COLD FRONT SHOULD NEARLY BISECT THE STATE FROM NE-SW AT
00Z...AND PUSH ACROSS THE LOWER SUSQ VALLEY THIS EVENING.
GEFS AND 00Z-06 OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS
ACROSS THE NW MTNS ACCOMPANYING THE FROPA. EVEN THE LOWER SUSQ
VALLEY COULD SEE A SHOWER IN SPOTS WITH THE EARLY EVENING FROPA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
UNDER A NARROW SFC HIGH...VERY LIGHT/CALM WINDS AND RESIDUAL LLVL
MSTR TRAPPED BLO INVERSION ARE SUPPORTING WIDESPREAD LOW CIGS AND
REDUCED VSBYS IN THE MVFR TO LIFR RANGE. LOOK FOR IMPROVING CONDS
DURING THE DAYLIGHT HOURS AS WSW WINDS BEGIN TO INCREASE AHEAD OF
A COLD FRONT APPROACHING FROM THE NW. THE FROPA WILL OCCUR FROM
NW TO SE THIS AFTN-EVE AND MAY BE ACCOMPANIED BY A BRIEF PD OF
-RA. A RETURN TO VFR IS PROJECTED FOR MOST SITES BY 00Z SUN.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
214 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE ACROSS THE LAUREL
HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT.
NOTHING MORE THAN SOME VERY PATCHY AND LIGHT DRIZZLE WILL OCCUR.
TEMPS WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST A DEG OR 2
IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME PARTIAL
CLEARING OCCURS.
FURTHERMORE...PARTIAL CLEARING IN ANY LOCATION COULD ALLOW
READINGS TO FALL JUST BLW FREEZING AND CREATE SOME ICY SPOTS ON
UNTREATED ROADS. ANY BREAKS IN THE CLOUD COVER COULD ALSO CREATE
MORE IN THE WAY OF PATCHY DENSE FOG.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE NEXT COLD AIRMASS WILL ARRIVE WITH A COLD FRONT THAT THE NEAR
TERM GUIDANCE SHOWS ENTERING MY NWRN ZONES BY AROUND MID DAY.
GEFS AND 18Z OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS ACROSS
THE NW MTNS AS FRONT COMES THRU. EVEN THE LOWER SUSQ VALLEY COULD
SEE A SHOWER IN SPOTS WITH THE LATE DAY FROPA.
A SURGE OF MILDER AIR AHEAD OF FRONT WILL PUSH READINGS TO NEAR
SEASONAL NORMS...DESPITE A GOOD DEAL OF CLOUDINESS. HIGHS SHOULD
RANGE FROM THE MID 40S TO LOWER 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SAT NIGHT INTO
MIDWEEK...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT WILL
BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW AROUND TO
THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS THE
NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
UNDER A NARROW SFC HIGH...VERY LIGHT/CALM WINDS AND RESIDUAL LLVL
MSTR TRAPPED BLO INVERSION ARE SUPPORTING WIDESPREAD LOW CIGS AND
REDUCED VSBYS IN THE MVFR TO LIFR RANGE. LOOK FOR IMPROVING CONDS
DURING THE DAYLIGHT HOURS AS WSW WINDS BEGIN TO INCREASE AHEAD OF
A COLD FRONT APPROACHING FROM THE NW. THE FROPA WILL OCCUR FROM
NW TO SE THIS AFTN-EVE AND MAY BE ACCOMPANIED BY A BRIEF PD OF
-RA. A RETURN TO VFR IS PROJECTED FOR MOST SITES BY 00Z SUN.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
131 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON LATE TODAY PASSAGE LATE THIS AFTERNOON AND THIS EVENING.
THIS FRONT WILL REINFORCE THE COLD AIR AND RESULT IN BELOW NORMAL
TEMPERATURES SUNDAY...THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE ACROSS THE LAUREL
HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT.
NOTHING MORE THAN SOME VERY PATCHY AND LIGHT DRIZZLE WILL OCCUR.
TEMPS WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST A DEG OR 2
IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME PARTIAL
CLEARING OCCURS.
FURTHERMORE...PARTIAL CLEARING IN ANY LOCATION COULD ALLOW
READINGS TO FALL JUST BLW FREEZING AND CREATE SOME ICY SPOTS ON
UNTREATED ROADS. ANY BREAKS IN THE CLOUD COVER COULD ALSO CREATE
MORE IN THE WAY OF PATCHY DENSE FOG.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE NEXT COLD AIRMASS WILL ARRIVE WITH A COLD FRONT THAT THE NEAR
TERM GUIDANCE SHOWS ENTERING MY NWRN ZONES BY AROUND MID DAY.
GEFS AND 18Z OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS ACROSS
THE NW MTNS AS FRONT COMES THRU. EVEN THE LOWER SUSQ VALLEY COULD
SEE A SHOWER IN SPOTS WITH THE LATE DAY FROPA.
A SURGE OF MILDER AIR AHEAD OF FRONT WILL PUSH READINGS TO NEAR
SEASONAL NORMS...DESPITE A GOOD DEAL OF CLOUDINESS. HIGHS SHOULD
RANGE FROM THE MID 40S TO LOWER 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SAT NIGHT INTO
MIDWEEK...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT WILL
BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW AROUND TO
THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS THE
NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
BEEN UPDATING TAFS AS NEEDED THIS EVENING.
EARLIER DISCUSSION BELOW.
WIDESPREAD IFR AND MVFR CONDITIONS EXPECTED OVERNIGHT INTO
SATURDAY MORNING.
CONDITIONS WILL SLOWLY IMPROVE LATER SATURDAY...AS WINDS PICK
UP FROM THE SW.
A COLD FRONT MOVES IN LATE SAT...A FEW RAIN OR SNOW SHOWERS
POSSIBLE ACROSS THE NORTH.
DRY AIR COMING IN SUNDAY WILL PREVAIL INTO TUE...AS HIGH
PRESSURE BUILDS EASTWARD.
PERHAPS A FEW RAIN SHOWERS ON WED.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...MAINLY VFR WITH SCATTERED RAIN SHOWERS.
&&
.CLIMATE...
SPRING OFFICIALLY BEGINS AT 645 PM EDT/2245 UTC THIS EVENING.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...RXR
AVIATION...MARTIN
CLIMATE...
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
949 PM CDT SUN MAR 22 2015
.UPDATE...
SKIES HAVE CLEARED...AND WINDS HAVE SUBSIDED. MANY LOCATIONS HAVE
ALREADY DIPPED INTO THE 50S...RAPIDLY APPROACHING DEW POINTS.
FOLLOWING A WIDESPREAD RAINFALL EVENT...THIS WOULD APPEAR THE
PERFECT RECIPE FOR FOG. HOWEVER...GUIDANCE IS A BIT GUN-SHY. THE
NAM PERFECT PROG IS THE MOST BULLISH...BLANKETING NEARLY THE
ENTIRE CWA IN DENSE FOG...BUT THE CORRESPONDING MOS IS FREE OF ANY
SIGNIFICANT RESTRICTIONS TO VISIBILITY. THE RAP AND HRRR INDICATE
SOME DENSE FOG...BUT NEITHER IS INCLINED FOR IT TO BE WIDESPREAD.
THE 00Z FWD RAOB SHOWS THAT THE MOIST LAYER IMMEDIATELY ADJACENT
TO THE SURFACE IS INCREDIBLY THIN. ALTHOUGH THE WINDS ARE
PROJECTED TO REMAIN LIGHT WITHIN A MILE OF THE SURFACE...EASILY
ASSURING ADEQUATE RADIATIONAL COOLING...EVEN A LIGHT BREEZE AT THE
SURFACE MAY BE ENOUGH TO ENTRAIN DRIER AIR JUST A FEW HUNDRED FEET
OFF THE DECK.
WHERE WINDS ARE CALM...EXPECT DEW WILL BEGIN TO FORM AS GROUND
TEMPS COOL MORE RAPIDLY THAN THE 2-METER TEMPS INDICATE. SHALLOW
FOG WILL THEN GRADUALLY DEVELOP. THE LOWEST VISIBILITIES WILL
FAVOR LOW-LYING AREAS...BODIES OF WATER...AND LOCATIONS WHERE THE
HEAVIEST RAINFALL AMOUNTS OCCURRED. BUT EVEN IN THESE AREAS...THE
DEPTH OF THE FOG WILL LIKELY BE LESS THAN A FEW HUNDRED FEET. IT
MAY TAKE ANOTHER SEVERAL HOURS (WELL AFTER MIDNIGHT) FOR ANY DENSE
FOG TO DEVELOP. AT THIS TIME...DO NOT EXPECT DENSE FOG WILL BE
WIDESPREAD ENOUGH TO WARRANT AN ADVISORY...BUT WILL CONTINUE TO
MONITOR TRENDS. IF FOG IS WELL ESTABLISHED BY MIDNIGHT...THE
LIKELIHOOD OF DENSE FOG DURING THE MORNING COMMUTE WILL INCREASE
CONSIDERABLY.
25
&&
.AVIATION...
/ISSUED 653 PM CDT SUN MAR 22 2015/
CONCERNS...AREAS OF FOG WILL DEVELOP OVERNIGHT...WITH POSSIBLE
IFR/LIFR CONDITIONS BEFORE DAYBREAK THAT WILL CONTINUE THROUGH
15-16Z.
VFR CONDITIONS RETURNED TO ALL OF THE TAF SITES SUNDAY AFTERNOON.
SKIES WILL CONTINUE TO CLEAR DURING THE NEXT COUPLE OF HOURS. WITH
CLEAR SKIES...LIGHT WINDS AND A MOIST GROUND...AREAS OF FOG WILL
DEVELOP OVERNIGHT. SOME LOCALLY DENSE FOG IS POSSIBLE. FOR
NOW...HAVE INDICATED 4SM BR BY 09Z AND 1SM BR BY 11Z. FOR THE
11-14Z PERIOD...HAVE SHOWN TEMPO 1/2SM FG OVC002...BUT WOULD NOT
BE SURPRISED IF THEY GO DOWN TO 1/4SM FG OVC001. THE FOG SHOULD BE
SHALLOW AND AN IMPROVEMENT TO VFR SHOULD OCCUR AROUND OR SHORTLY
AFTER 16Z. DFW HAS ALREADY GONE TO SOUTH FLOW...AND THIS SHOULD
CONTINUE THROUGH THE NEXT 36 HOURS.
EXPECT A SIMILAR SCENARIO AT WACO...WITH AREAS OF FOG DEVELOPING
AROUND 07Z...AND VISIBILITIES DROPPING TO 1SM BY 09Z. HAVE
INDICATED A TEMPO 1/2SM FG OVC002 FOR THE 10-14Z PERIOD WITH AN
IMPROVEMENT TO VFR 16-17Z. NORTH WINDS AT LESS THAN 10 KNOTS WILL
BECOME LIGHT AND VARIABLE OVERNIGHT...AND SOUTHEAST 5 TO 8 KNOTS
BY 15Z MONDAY.
58
&&
.PREV DISCUSSION... /ISSUED 342 PM CDT SUN MAR 22 2015/
WATER VAPOR SATELLITE IMAGERY SHOWED A SHORTWAVE TROUGH OVER THE
ARKLATEX AREA...MOVING EAST-NORTHEAST AWAY FROM NORTH TEXAS.
BEHIND THIS TROUGH...LARGE SCALE FORCING FOR SUBSIDENCE WAS
BEGINNING TO CLEAR OUT THICK CLOUD COVER OVER NORTH TEXAS THIS
AFTERNOON. AT THE SURFACE...A RIDGE OF HIGH PRESSURE WAS IN PLACE
OVER NORTH TEXAS...RESULTING IN LIGHT NORTHERLY WINDS FOR MOST
LOCATIONS.
FOR TONIGHT...SKIES ARE EXPECTED TO BECOME MOSTLY CLEAR AS LARGE
SCALE FORCING FOR SUBSIDENCE CONTINUES OVER THE REGION. HIGH
PRESSURE AT THE SURFACE IS EXPECTED TO MOVE SLIGHTLY EAST
TONIGHT...RESULTING IN VERY LIGHT EAST TO SOUTHEASTERLY WINDS
ACROSS THE CWA. IF SUBSIDENCE IS ABLE TO CLEAR OUT SKIES
TONIGHT...AN IDEAL ENVIRONMENT FOR RADIATIONAL COOLING IS
EXPECTED TO BRING TEMPERATURES DOWN INTO THE UPPER 40S TO LOWER
50S BY MONDAY MORNING. WITH DEW POINT VALUES THIS AFTERNOON
OBSERVED IN THE LOWER TO MID 50S ACROSS THE AREA...TEMPERATURES
ARE EXPECTED TO BECOME COLD ENOUGH...AND WINDS ARE EXPECTED TO
REMAIN LIGHT ENOUGH...FOR AREAS OF FOG TO DEVELOP BEFORE SUNRISE
TOMORROW MORNING. THE THICKNESS OF THE FOG WILL DEPEND ON JUST HOW
MUCH CLOUD COVER CAN CLEAR OUT TONIGHT.
IF SKIES BECOME CLEAR...CHANCES ARE HIGH THAT DENSE FOG WILL
DEVELOP ACROSS THE REGION BY EARLY TOMORROW MORNING...AND A DENSE
FOG WILL NEED TO BE ISSUED AS A RESULT. HELD OFF ON ISSUING A
DENSE FOG ADVISORY FOR NOW AS WE`D LIKE TO SEE THE SUBSIDENCE
ACTUALLY CLEAR OUT THE CLOUDS BEFORE BUYING IN ON AREAS OF DENSE
FOG. SOME FOG IS LIKELY TO DEVELOP REGARDLESS OF HOW MUCH CLOUD
COVER REMAINS IN PLACE...HOWEVER GETTING WIDESPREAD VISIBILITIES
DOWN TO ONE QUARTER MILE OR BELOW WILL BE DIFFICULT WITHOUT CLEAR
SKIES TONIGHT.
UPPER LEVEL RIDGING IS EXPECTED TO BUILD OVER THE REGION ON
MONDAY...WHICH WILL SUPPORT MOSTLY SUNNY SKIES AND TEMPERATURES
CLIMBING 10 TO 15 DEGREES WARMER THAN TODAY. WINDS ARE EXPECTED TO
VEER AROUND TO THE SOUTH WHICH WILL HELP KEEP LOW- LEVEL MOISTURE
IN PLACE...AND SEND SOME ADDITIONAL GULF MOISTURE INTO THE REGION
FOR TUESDAY AND WEDNESDAY.
ON TUESDAY...A SHORTWAVE TROUGH CURRENTLY LOCATED APPROXIMATELY
400 MILES WEST OF THE NORTHERN CALIFORNIA COAST IS EXPECTED TO
MOVE EAST OVER THE CENTRAL PLAINS...SENDING A PACIFIC-TYPE COLD
FRONT SOUTHEAST ACROSS THE SOUTHERN HIGH PLAINS TOWARDS NORTH
TEXAS. THIS BOUNDARY IS EXPECTED TO STALL OUT IN THE NORTHWEST
PORTIONS OF THE CWA TUESDAY AFTERNOON. DOWNSLOPE FLOW AND DRIER
AIR BEHIND THIS BOUNDARY WILL RESULT IN TEMPERATURES CLIMBING INTO
THE UPPER 80S OVER THE WESTERN QUARTER OF THE CWA. TEMPERATURES
ARE EXPECTED TO CLIMB TO RIGHT AROUND 80 DEGREES TO THE EAST
WHERE LOW-LEVEL MOISTURE AND SOME AFTERNOON CUMULUS CLOUDS WILL
LIKELY REMAIN IN PLACE.
THERE WILL BE SOME LIFT ALONG THE STALLED OUT BOUNDARY ON
TUESDAY...HOWEVER FORECAST SOUNDINGS INDICATE THAT A SUBSTANTIAL
CAP WILL BE IN PLACE. THIS CAP APPEARS TO BE STOUT ENOUGH TO
PREVENT THUNDERSTORMS FROM DEVELOPING ACROSS NORTH TEXAS TUESDAY
AFTERNOON...HOWEVER MODEL OUTPUT FROM THE ECMWF/GFS/NAM HINT AT A
SUFFICIENT AMOUNT OF LIFT TO TRIGGER THE SHALLOW CONVECTION
SCHEMES OF THESE MODELS. THIS CAN BE VISUALIZED AS A SUDDEN
INCREASE IN RELATIVE HUMIDITY IN THE MIDDLE TROPOSPHERE AROUND 00Z
WEDNESDAY (WHICH IS TUESDAY 7 PM). BECAUSE THE FORECAST SOUNDINGS
ARE ADVERTISING A STOUT CAP...AND MODELS ARE ADVERTISING
RELATIVELY WEAK LIFT ALONG THE BOUNDARY...DECIDED TO ONLY MENTION
A 10 PERCENT CHANCE OF STORMS NEAR THE STALLED OUT BOUNDARY
TUESDAY AFTERNOON AND EVENING. IF A STORM WAS ABLE TO
DEVELOP...THERE IS A CHANCE IT WOULD BE STRONG OR SEVERE WITH CAPE
VALUES FORECAST TO BE IN THE NEIGHBORHOOD OF 1500-2000 J/KG AND
DEEP LAYER BULK SHEAR OF AROUND 35 KTS. CHANCES ARE WE WILL NOT
SEE STORMS THIS FAR SOUTH HOWEVER. EXPECT MOST THUNDERSTORM
ACTIVITY WILL REMAIN IN OKLAHOMA...CLOSER TO THE SHORTWAVE TROUGH.
ANOTHER STRONG SHORTWAVE TROUGH IS EXPECTED TO MOVE OVER THE
PLAINS WEDNESDAY AFTERNOON AND EVENING. THIS TROUGH IS EXPECTED TO
SPREAD STRONG FORCING FOR ASCENT AS FAR SOUTH AS THE RED
RIVER...SO OUR CHANCES FOR STORMS ALONG THE PACIFIC-FRONT OR
DRYLINE ARE BETTER AS A RESULT. FORECAST SOUNDINGS CONSISTENTLY
ADVERTISE A STRONG CAP IN PLACE OVER THE REGION ON WEDNESDAY...SO
EXPECT THAT IF ANY STORMS DEVELOP...THEY WILL REMAIN CLOSELY TIED
TO THE FRONT. WITH STRONGER LIFT EXPECTED...WENT AHEAD WITH A 20
TO 30 PERCENT CHANCE OF STORMS WEDNESDAY AFTERNOON...GENERALLY
WEST AND NORTHWEST OF THE DFW METROPLEX. THE SHORTWAVE TROUGH
WILL EVENTUALLY SEND THE STALLED OUT PACIFIC-TYPE COLD FRONT
SOUTHEAST ACROSS NORTH TEXAS FROM WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. ONCE THE FRONT STARTS MOVING...THUNDERSTORMS ARE
EXPECTED TO GROW UPSCALE ALONG THE FRONT INTO A SQUALL LINE AND
ACCOMPANY THE FRONT SOUTHEAST ACROSS THE CWA.
IF STORMS ARE ABLE TO DEVELOP WEDNESDAY AFTERNOON BEFORE THE FRONT
STARTS TO MOVE...STORMS WILL HAVE A GOOD CHANCE AT BECOMING
ORGANIZED QUICKLY INTO STRONG TO SEVERE STORMS. CAPE VALUES ARE
EXPECTED TO CLIMB TO 2000 TO 2500 J/KG WHILE DEEP LAYER BULK SHEAR
VALUES CLIMB TO 45 TO 50 KTS. THE COMBINATION OF THESE
PARAMETERS...THE FORCING FOR ASCENT LIMITED TO A RELATIVELY SMALL
AREA NEAR THE STALLED OUT BOUNDARY...AND THE CAP IN PLACE WOULD
INITIALLY FAVOR A DISCRETE STORM MODE WEDNESDAY AFTERNOON.
IF STORMS ARE ABLE TO DEVELOP...THIS WOULD PROBABLY SUPPORT A
RISK OF DISCRETE SUPERCELLS UNTIL THE FRONT STARTS TO MOVE
WEDNESDAY EVENING. ONCE THE FRONT MOVES...STRONGER LIFT SHOULD
WEAKEN THE CAP OVER A LARGER AREA RESULTING IN THE UPSCALE GROWTH
OF DISCRETE STORMS INTO A SQUALL LINE. HAIL AND DAMAGING WINDS
LOOK TO BE THE PRIMARY THREATS ASSOCIATED WITH ANY SEVERE STORMS
ON WEDNESDAY...TRANSITIONING OVER TO PRIMARILY A DAMAGING WIND
THREAT WEDNESDAY EVENING AND OVERNIGHT.
IT IS TOO EARLY TO REALLY ASSESS THE TORNADO THREAT...HOWEVER A
QUICK LOOK AT PARAMETERS SHOWS LOW-LEVEL SHEAR VALUES ARE
SOMEWHAT MEAGER...SO CURRENT THINKING IS THAT THE PRIMARY SEVERE
WEATHER THREATS ARE DAMAGING WINDS AND HAIL. THIS MAY CHANGE AS WE
GET CLOSER TO WEDNESDAY OF COURSE AND CAN ASSESS SMALLER SCALE
FEATURES. WHILE FLOODING DOES NOT APPEAR TO BE A WIDESPREAD
CONCERN WITH STORMS REMAINING CLOSELY TIED TO A MOVING
FRONT...LOCALLY HEAVY RAINFALL/FLOODING IS CERTAINLY A POSSIBILITY
ASSUMING A SQUALL LINE DEVELOPS AND MOVES SOUTHEAST ACROSS MUCH OF
THE CWA.
BEHIND THE FRONT...DRIER AIR IS EXPECTED TO BUILD INTO THE
REGION...WHICH SHOULD RESULT IN A DRY FORECAST FOR THE REMAINDER
OF THE WEEK. TEMPERATURES ARE EXPECTED TO BE BELOW NORMAL AT THE
END OF THE WEEK BEHIND THE FRONT WITH A COOLER AND DRIER AIR MASS
IN PLACE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 49 76 59 81 60 / 0 0 5 10 10
WACO, TX 48 77 57 80 59 / 0 0 5 5 10
PARIS, TX 46 74 52 77 56 / 0 0 5 5 20
DENTON, TX 48 76 58 82 57 / 0 0 5 10 10
MCKINNEY, TX 47 75 56 79 58 / 0 0 5 10 20
DALLAS, TX 51 76 59 80 61 / 0 0 5 10 10
TERRELL, TX 47 75 56 78 59 / 0 0 5 5 10
CORSICANA, TX 49 76 56 79 60 / 0 0 5 5 10
TEMPLE, TX 50 77 56 79 58 / 0 0 5 5 5
MINERAL WELLS, TX 49 79 59 85 56 / 0 0 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
58/25
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1201 AM CDT SAT MAR 21 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...BRO AND HRL AT LIFR WITH OVC LOW CEILINGS WHILE MFE
AWAY FROM THE COAST REMAINS VFR. MARINE AND COASTAL FOG WILL
COMPLICATE AVIATION CONDITIONS AGAIN THIS TAF CYCLE...ALONG WITH
LOW CIGS. LIGHT SOUTHEAST WINDS WILL PREVAIL THE REST OF THE NIGHT
WHILE DEW POINTS ARE IN THE MUGGY UPPER 60S TO LOWER 70S. WINDS
WILL ATTEMPT TO SWITCH TO NORTH SOMETIME DURING THE DAY AS A COLD
FRONT MEANDERS SOUTH INTO THE AREA...BUT WITH HIGH RAIN CHANCES
TODAY...LOW CEILINGS AND REDUCED VISIBILITY SHOULD KEEP THE TAFS
IFR.
&&
.PREV DISCUSSION... /ISSUED 948 PM CDT FRI MAR 20 2015/
DISCUSSION...THE COMBINATION OF SURFACE OBS AND WEB CAM IMAGES
FROM SPI INDICATES THAT VSBYS ARE FALLING STEADILY DUE TO THE WAA
COMING IN FROM THE SE OVER FAIRLY COOLER SURF AND BAY WATER TEMPS
IN THE MID 60S. SO WILL POST UP A DENSE FOG ADVISORY FOR THE
LAGUNA MADRE...LOWER TX GULF WATERS OUT TO 20 NM OFFSHORE AND FOR
COASTAL WILLACY AND COASTAL CAMERON COUNTIES THROUGH 7 AM
TOMORROW.
CONCERNING THE MAIN SHORT TERM THREAT...HEAVY RAINFALL...THE SHORT
RANGE HRRR GUIDANCE MAINTAINS THE THREAT OF LOCALLY HEAVY RAINFALL
OVER PORTIONS OF THE NORTHERN AND WESTERN COUNTIES THROUGHOUT LATE
TONIGHT INTO SATURDAY MORNING. THE RAINFALL WILL EXPAND FURTHER
EAST AND SOUTH THROUGHOUT SATURDAY AS THE 500 MB CLOSED LOW TO OUR
WEST OPENS UP AND PUSHES EAST ACROSS TX SAT AND SAT NIGHT. SPC
MAINTAINS A MARGINAL THREAT FOR SVR T-STORMS THROUGHOUT SATURDAY
AS THE PWATS...CAPE VALUES AND BULK SHEAR INCREASE OVER THE
REGION. THE MAIN THREAT FROM ANY OF THE STRONGER CONVECTION THAT
FORMS WILL BE MAINLY FROM GUSTY WINDS AND POSSIBLE SEVERE HAIL.
FOR NOW WILL NOT MAKE ANY OTHER MAJOR CHANGES TO THE ONGOING
FORECAST WORDING. THE CURRENT FFA IN EFFECT MAY NEED TO BE
ADJUSTED OR POSSIBLY EXPANDED THROUGH THE OVERNIGHT HOURS TO
ACCOUNT FOR THE NEAR TERM CONV TRENDS OVERNIGHT.
PREV DISCUSSION... /ISSUED 755 PM CDT FRI MAR 20 2015/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...A FAIRLY COMPLEX AVIATION SITUATION IS SETTING UP
OVER THE NEXT 24 HOURS AS THE DEEP 500 MB TROUGH AXIS TO THE WEST
OF SOUTH TX DIGS EAST. THE APPROACH OF THIS TROUGH AXIS WILL
STEADILY DEEPEN THE PWAT AND CAPE VALUES THROUGHOUT TONIGHT AND
SATURDAY LIKELY RESULTING IN INCREASING CONV COVERAGE ACROSS THE
RGV AIPPORTS DURING THE LATTER HALF OF THE CURRENT TAF SETS AS THE
UPPER LEVEL SUPPORT INCREASES. THIS WILL RESULT IN PERIODS OF
VFR/MVFR CONDITIONS WITH PERIODS OF IFR CEILINGS/VSBYS DUE TO
PERIODS OF THE STRONGER CONV MAINLY AFTER 12Z SAT. IN THE EARLIER
TAF PERIODS EXPECT THE LOW LEVEL WAA MOVING OVER THE COOLER
NEARSHORE WATERS NEAR SPI TO ALLOW AREAS OF LOW CLOUDS AND VSBYS
TO REFORM AND ADVECT WESTWARDS LATER TONIGHT REUSLTING IN
IFR/LIFR CEILINGS FOR ALL THREE RGV AIRPORTS.
PREV DISCUSSION... /ISSUED 323 PM CDT FRI MAR 20 2015/
SHORT TERM /NOW THROUGH SATURDAY NIGHT/...LATEST WATER VAPOR
IMAGERY SHOWS A 500MB LOW OVER BAJA CALIFORNIA WITH ABUNDANT PACIFIC
MOISTURE STREAMING ACROSS THE AREA FROM THE SOUTHWEST. BRO RADAR
SHOWS SOME WEAK ECHOS ACROSS THE RIO GRANDE RIVER...SOUTH OF ZAPATA.
CURRENT SURFACE ANALYSIS SHOWS A WEAK COLD FRONT ACROSS THE HILL
COUNTRY THIS AFTERNOON. SURFACE OBSERVATIONS AND WEBCAMS ON SOUTH
PADRE ISLAND INDICATE LIGHT FOG/HAZE ALONG THE LOWER TEXAS...WITH
VISIBILITIES RANGING BETWEEN 5 TO 6 MILES. HOWEVER...THICKER SEA FOG
CONTINUES OVER THE NEAR SHORE GULF WATERS 0 TO 20 NM EAST OF PADRE
ISLAND.
TONIGHT...THE CUT OFF LOW WILL EJECT SLOWLY EAST INTO NORTHWEST
MEXICO. DEEP LAYERED SOUTHWEST FLOW WILL CONTINUE TO ADVECT GULF AND
PACIFIC MOISTURE THE REGION. THE WEAK COLD FRONT WILL SLOWLY MOVE
INTO THE RANCHLANDS LATER TONIGHT. THE WEAK SURFACE FRONT COMBINED
WITH ENERGY ALOFT WILL PROVIDE THE OPPORTUNITY FOR HEAVY RAIN...
ESPECIALLY ACROSS THE NORTHERN RANCHLANDS...FOR TONIGHT INTO
SATURDAY. THE LATEST WPC QPF VALUES PAINTS BETWEEN 1 TO 3
INCHES...LOCALLY UP TO 4 INCHES...ACROSS THE WESTERN PORTIONS OF
DEEP SOUTH TEXAS. DUE TO RECENT RAINS AND EXPECTED HEAVY RAINS...A
FLASH FLOOD WATCH HAS BEEN ISSUED FOR BROOKS...JIM HOGG AND ZAPATA
COUNTIES BEGINNING THIS EVENING AT 7 PM.
RAINFALL WILL INCREASE ACROSS THE WESTERN BRUSH COUNTRY INTO THE
UPPER VALLEY TONIGHT. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE ACROSS THE LOWER VALLEY..ESPECIALLY AFTER MIDNIGHT.
FOG WILL BE A CONCERN AGAIN TONIGHT ALONG THE COAST AND ACROSS THE
NEAR SHORE GULF WATERS TONIGHT DUE TO LIGHT WINDS AND HIGH
DEWPOINTS. AREAS OF FOG...LOCALLY DENSE FOG NEAR THE
COAST...EXPECTED TONIGHT. LOW TEMPERATURES TONIGHT WILL BE NEAR
NORMAL...IN THE MID 60S...UNDER CLOUDY SKIES.
SATURDAY AND SATURDAY NIGHT...THE 500MB LOW MOVES TOWARDS THE BIG
BEND REGION SATURDAY AND INTO NORTHERN TEXAS BY SATURDAY NIGHT.
SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS DEEP SOUTH TEXAS WITH
THE BEST LIFT OCCURRING SATURDAY INTO SATURDAY NIGHT. SPC SHOWS A
MARGINAL RISK OF SEVERE THUNDERSTORMS...GENERALLY ALONG AND EAST OF
I-69C/HWY 281 SATURDAY INTO SATURDAY NIGHT. THE MAIN IMPACTS WITH
THIS ACTIVITY WILL BE HEAVY RAIN...GUSTY WINDS AND SMALL HAIL...DIME
SIZE OR LESS. THE WEAK FRONT DRAPED ACROSS THE REGION SATURDAY NIGHT
WILL RESULT IN VERY LIGHT WINDS. THIS WILL RESULT IN AREAS OF
FOG...SOME LOCALLY DENSE...ALONG THE COAST. HIGH TEMPERATURES
SATURDAY WILL BE IN THE 70S WITH UPPER 60S ALONG THE COAST.
OVERNIGHT LOW TEMPERATURES SATURDAY NIGHT WILL BE IN THE UPPER 50S
ACROSS THE RANCHLANDS TO THE MID 60S NEAR THE COAST.
LONG TERM /SUNDAY THROUGH FRIDAY/...DRIER AIR WILL MOVE INTO
SOUTHWEST TEXAS SUNDAY BRINGING AN END TO THE RAIN CHANCES ACROSS
THE CWA AS THE 500MB SHORTWAVE TROUGH ACROSS TEXAS MOVES EASTWARD
AND THE SOUTHWEST FLOW ALOFT VEERS TO THE WEST AND NORTHWEST
PROVIDING SUBSIDENCE ACROSS THE WESTERN HALF OF THE STATE. AT THE
SURFACE...THE WEAK COLD FRONT WILL MOVE THROUGH THE RIO GRANDE
VALLEY SUN AFTERNOON. WARM AND RELATIVELY DRY CONDITIONS SHOULD
PREVAIL ACROSS SOUTH TX MONDAY THROUGH WEDNESDAY WITH A NEARLY
ZONAL FLOW PREVAILING ACROSS THE SOUTHERN UNITED STATES. A 500MB
TROUGH IS EXPECTED TO DEVELOP ACROSS THE CENTRAL U.S. AND A 500MB
TROUGH/LOW IS ALSO EXPECTED TO DEVELOP ACROSS BAJA CALIFORNIA
WEDNESDAY INTO THURSDAY. LOW TO MID LEVEL MOISTURE IS PROGGED TO
INCREASE ACROSS SOUTH TX WEDNESDAY AND THURSDAY BEFORE A COLD
FRONT MOVES THROUGH THE RIO GRANDE VALLEY THURS NIGHT INTO FRI
MORNING. THERE ARE STILL SOME DIFFERENCES BETWEEN THE ECMWF AND
THE GFS ON THE TIMING OF THIS FRONT. WILL MENTION A SLIGHT CHANCE
TO CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY AND A CHANCE OF
SHOWERS FRIDAY AS MOISTURE POOLS ALONG AND AHEAD OF THE FRONT
THROUGH THE REST OF THE FORECAST PERIOD.
MARINE...
NOW THROUGH SATURDAY NIGHT...SHOWERS AND THUNDERSTORMS POSSIBLE
SATURDAY AND SATURDAY NIGHT AS A WEAK COLD FRONT APPROACHES THE
LOWER TEXAS COASTAL WATERS. LIGHT TO MODERATE SOUTHEAST WINDS AND
LOW SEAS WILL PREVAIL THROUGH THE FORECAST PERIOD.
SUNDAY THROUGH WEDNESDAY...LIGHT SOUTH WINDS WILL PREVAIL ACROSS
THE COASTAL WATERS SUNDAY BEFORE A WEAK COLD FRONT MOVES OFFSHORE
THE LOWER TEXAS COAST SUN AFTERNOON. WINDS WILL SHIFT TO THE
NORTHWEST SUN AFTERNOON BUT BECOME LIGHT AND VARIABLE SUN NIGHT.
THE WINDS WILL INCREASE FROM THE NORTH AS HIGH PRESSURE FINALLY
BUILDS INTO THE WESTERN GULF OF MEXICO MONDAY IN THE WAKE OF THE
FRONTAL SYSTEM OVER EAST TX SUNDAY MOVING EASTWARD MONDAY. LIGHT
TO MODERATE NORTH WINDS MONDAY WILL VEER TO THE SOUTHEAST TUESDAY
AS THE SURFACE RIDGE MOVES QUICKLY EASTWARD. LIGHT TO MODERATE
SOUTHEAST WINDS SHOULD PREVAIL ACROSS THE LOWER TX COAST TUESDAY
INTO WEDNESDAY.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR TXZ248>250.
DENSE FOG ADVISORY UNTIL 7 AM CDT SATURDAY FOR TXZ256-257.
GM...DENSE FOG ADVISORY UNTIL 7 AM CDT SATURDAY FOR GMZ130-132-135-
150-155.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
54/55
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
750 PM EDT SUN MAR 22 2015
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO WEDGE AGAINST THE EASTERN FACE OF
THE APPALACHIANS THIS EVENING AND TONIGHT. EXPECT A WEAK
DISTURBANCE TO GRAZE THE SOUTHERN EDGE OF OUR AREA TONIGHT...
BRINGING THE POTENTIAL FOR LIGHT RAIN AND DRIZZLE TO NORTHERN
NORTH CAROLINA...AND ALONG THE BLUE RIDGE TOWARD ROANOKE. A WARM
FRONT WILL LIFT NORTHEAST ACROSS THE REGION TUESDAY AHEAD OF A
STRONG COLD FRONT THAT WILL AFFECT THE REGION BY THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 735 PM EDT SUNDAY...
CLOUDS OF THE MID AND HIGH VARIETY CONTINUE TO OVERSPREAD THE SKY
EARLY THIS EVENING. RADAR SHOWING THE MID LEVEL MOISTURE INTO THE
NC AREA...WITH SFC OBS REPORTING SPRINKLES AS FAR NORTH AS
MORGANTON NC. GIVEN DRY AIR IN PLACE...HAVE SLOWED DOWN ONSET OF
SLIGHT/LOW CHANCE POPS A FEW HOURS. THE LATEST RAP SHOWING LACK OF
DEEP LOW LVL MOISTURE EVEN INTO BOONE TONIGHT...AND FEEL THAT
DRIZZLE MAY NOT FORM...AND LOOKING MORE AT SPRINKLES/VERY LIGHT
RAIN. DID NOT CHANGE ANYTHING BEYOND MIDNIGHT THOUGH AT THIS
POINT.
PREVIOUS VALID DISCUSSION...
WINDS ASSOCIATED WITH THE HIGH PRESSURE WEDGE WILL SHIFT EAST
NORTHEASTERLY WHICH WILL FACTOR INTO OUR WEATHER CONDITIONS
THROUGH MONDAY EVENING.
COLD AIR BUILDING IN WITH THE HIGH PRESSURE WEDGE WILL DRIVE
OVERNIGHT TEMPERATURES INTO THE UPPER 20S NEAR INTERSTATE
64...WHILE THE FOOTHILLS OF NORTH CAROLINA WILL HOLD IN THE LOW TO
MID 40S. TEMPERATURES ALONG THE BLUE RIDGE PARKWAY...WHICH IS
EMBEDDED WITHIN THE COLD AIR BEING PUSHED IN BY THE WEDGE...WILL
FALL INTO THE LOW TO MID 30S...WHICH MAY RESULT IN POCKETS OF
FREEZING DRIZZLE OR FREEZING FOG WHERE TEMPERATURES FALL TO
FREEZING. DO NOT EXPECT ANY ICING TO ACCUMULATE ON ROADWAY
SURFACES HOWEVER AS THEY WILL REMAIN TOO WARM. HAVE MADE MENTION
OF THIS IN THE HAZARDOUS WEATHER OUTLOOK.
THE HIGH PRESSURE WEDGE WILL REMAIN IN PLACE FOR MONDAY...
MAINTAINING A COOL FLOW OFF THE ATLANTIC. BELIEVE LOW CLOUDS WILL
HANG ACROSS THE AREA THROUGH MUCH OF THE DAY DESPITE FOG AND
DRIZZLE DISSIPATING BY EARLY AFTERNOON...EXCEPT PERHAPS IN THE
VICINITY OF THE BLUE RIDGE PARKWAY. AS SUCH...EXPECT A COOLER DAY
COMPARED TO SUNDAY...WITH AFTERNOON HIGHS LIMITED TO THE UPPER
40S TO LOW 50S. THE EXCEPTION MAY BE PORTIONS OF WESTERN TAZEWELL
COUNTY...WHICH IS SEPARATED FROM THE INFLUENCE OF THE WEDGE BY
TERRAIN...WHERE HIGHS WILL APPROACH 60.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 335 PM EDT SUNDAY...
WEAK UPPER WAVE WITH FAIRLY DEEP MOISTURE CROSSING THE MID
ATLANTIC REGION ON TUESDAY...FOLLOWED BY MID AND HIGH CLOUDS
TRAILING OUT OF THE OHIO VALLEY AND GREAT LAKES ALONG THE WARM
FRONT ON TUESDAY.
BY LATE WEDNESDAY FORECAST AREA WILL BE WELL INTO THE WARM SECTOR
WITH DEEP SOUTHWEST FLOW. DEW POINTS WILL BE RISING AS MOISTURE IS
BROUGHT UP FROM THE GULF.
WITH THE SURFACE HIGH OFF THE SOUTHEAST COAST...MODELS WERE
SUGGESTING A MARINE/STRATUS TYPE LAYER MOVING INTO THE PIEDMONT FROM
THE SOUTHEAST ON TUESDAY NIGHT AND WEDNESDAY MORNING. WILL BE
INCREASING THE CLOUD COVER DURING THIS TIME FRAME TO ACCOUNT FOR
THIS ADVECTION.
WEDGE AND CLOUD COVER ON TUESDAY WILL HOLD MAXIMUM TEMPERATURES
BELOW NORMAL. WILL AGAIN GO WITH COOLER MAV NUMBERS AS GUIDANCE
FOR HIGHS. ON WEDNESDAY...MODELS HAVE MOST OF THE WEDGE GONE AND A
MUCH WARMER AIR MASS WILL BE IN PLACE. BIGGEST IMPACT ON THE
TEMPERATURES WILL THEN DEPEND ON THE AMOUNT OF CLOUD COVER AND HOW
LONG IT TAKES WEDGE TO ERODE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 1245 PM EDT SUNDAY...
UPPER PATTERN TRANSITIONS FROM A WEAK RIDGE OVER THE EASTERN UNITED
STATES TO A DEEP LONG WAVE TROF BETWEEN WEDNESDAY NIGHT AND
SATURDAY.
SURFACE HIGH PRESSURE THAT BUILDS IN BEHIND THE FRONT WILL CROSS THE
OHIO AND TENNESSEE VALLEYS ON SATURDAY NIGHT...THEN WILL BE OVER THE
SOUTHEAST UNITED STATES ON SUNDAY. THIS WILL ALSO LEAD IN THE
STRONGEST PUSH OF COLD AIR THIS WEEK...FOR FRIDAY NIGHT AND
SATURDAY. ECMWF HAS 850MB TEMPERATURES DROPPING TO TO THE -6 TO -10
RANGE FOR SATURDAY AND SUNDAY. WITH THAT MUCH COLD AIR
AVAILABLE...STILL MONITORING THE POTENTIAL FOR WINTER WEATHER...
POSSIBLY FRIDAY NIGHT. WILL KEEP SATURDAY NIGHT AND SUNDAY DRY FOR
NOW AS NEXT LOW PRESSURE SYSTEM TRACKS ACROSS THE GREAT LAKES.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 730 PM EDT SUNDAY...
CIGS WILL BE VFR OF THE MID/HIGH CLOUD VARIETY THIS EVENING BEFORE
LOWERING CIGS ACROSS THE ROA/BCB AND POINTS SOUTH OVERNIGHT. THINK
MOST SITES WILL STAY VFR...THOUGH BCB/ROA AND POSSIBLY DAN WILL
DROP TO MVFR BETWEEN 07-09Z. FOLLOWED CLOSER TO THE RAP/RUC MODEL
BLENDED WITH THE NAM. THINK THE CIGS WILL BE LIFTING BY LATE
MORNING DESPITE THE WEDGE TO VFR.
WINDS WILL BECOME MORE EASTERLY AS THE CENTER OF HIGH PRESSURE
SHIFTS OVER UPPER NEW ENGLAND.
MAY SEE SUB-VFR CONDITIONS MONDAY NIGHT INTO TUESDAY AS THE WEDGE
ONLY SLOWLY WEAKENS AND RESIDUAL MOISTURE REMAINS TRAPPED ALONG
AND NEAR THE BLUE RIDGE. A WARM FRONT SHOULD FINALLY LIFT
NORTHEAST ACROSS THE REGION TUESDAY NIGHT...RESULTING IN DEEPENING
SOUTH TO SOUTHWEST FLOW...ALLOWING FOR IMPROVEMENT TO VFR AHEAD OF
ANOTHER COLD FRONT TO THE WEST ON WEDNESDAY. THIS FRONT IS
EXPECTED TO MOVE INTO OUR AREA WEDNESDAY NIGHT INTO
THURSDAY...WITH SHOWERS EXPECTED TO BE SCATTERED TO...AT TIMES...
NUMEROUS...WITH POTENTIAL FOR FRONTAL SLOWDOWN FRIDAY WITH
LINGERING SHOWERS AND SUB VFR CIGS IN THE MTNS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...NF
NEAR TERM...NF/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...JH/NF/WP
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
809 PM CDT SUN MAR 22 2015
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 808 PM CDT SUN MAR 22 2015
RADARS THIS EVENING SHOW A STRONG FGEN BAND OF SNOW FROM CENTRAL
MINNESOTA TO SOUTHWEST WISCONSIN TO NORTHERN ILLINOIS. SHORT WAVE
OVER SOUTHEAST MINNESOTA ALONG THIS BAND WILL PRODUCE A SWATH OF
HEAVY SNOW WITH IT ALONG WITH THE BAND ITSELF. QUESTION FOR
CENTRAL WISCONSIN IS HOW MUCH SNOW ACCUMULATION WILL REACH THE
AREA. DRY FEED OF AIR CONTINUES TO ERODE OR HOLD OF WESTERN
ADVANCEMENT OF SNOW INTO CENTRAL WISCONSIN. HAVE ALREADY DELAYED
ARRIVAL A BIT THROUGH EARLY EVENING. BUT STILL OVERALL THEME OF A
MINOR ACCUMULATION FOR AREAS SOUTHWEST OF A LINE FROM MFI TO OSH
LOOKS REASONABLE FOR TONIGHT SO LITTLE CHANGES LIKELY NEEDED REST
OF TONIGHT.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 244 PM CDT SUN MAR 22 2015
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LIGHT TO
MODERATE SNOW OCCURRING OVER SOUTHEAST MINNESOTA...SOUTHWEST
WISCONSIN...AND NORTHEAST IOWA EARLY THIS AFTERNOON ALONG THE
SOUTHWEST FLANK OF A POLAR AIRMASS. ANOTHER AREA OF SNOW EXISTS
OVER THE EASTERN DAKOTAS AHEAD OF A COMPACT SHORTWAVE TROUGH. DRY
AIR EMANATING FROM A CANADIAN HIGH CENTERED OVER THE GREAT LAKES HAS
PREVENTED THE SNOW FROM REACHING THE GROUND OVER CENTRAL WISCONSIN
DESPITE SOME RETURNS ON RADAR EARLIER. AS THE SHORTWAVE OVER THE
DAKOTAS MOVES EAST...SNOW AND ACCUMULATION CHANCES ARE THE MAIN
FORECAST CONCERNS.
TONIGHT...800-700MB THERMAL GRADIENT WILL CONTINUE TO BE ACTIVE
EARLY THIS EVENING OVER SOUTHWEST WISCONSIN. BUT THE MAIN PUSH OF
SNOW WILL BE EXITING MINNESOTA BY MID TO LATE EVENING AHEAD OF A
SHORTWAVE TROUGH...IN CONJUNCTION WITH MID-LEVEL FGEN ON THE NOSE OF
A 25KT LLJ AND A COUPLED JET STRUCTURE. CENTRAL WISCONSIN WILL BE
ON THE NORTHERN FRINGE OF THE AREA OF SNOW WHERE LOW LEVEL EASTERLY
WINDS WILL BE FEEDING IN DRY AIR. SOUNDINGS BECOME SATURATED ABOVE
750MB BY 06Z ACCORDING TO THE NAM...WHILE THE MESOMODELS AND SREF
ARE SLIGHTLY MORE AGGRESSIVE BRINGING IN PRECIP BY THIS TIME INTO
WOOD COUNTY. AS A RESULT...WILL INCREASE PRECIP CHANCES IN THAT
CENTRAL WISCONSIN AREA IN THE 06-09Z PERIOD. ACCUMULATIONS COULD
REACH UP TO AN INCH IN WOOD COUNTY BUT ONLY A TENTH OR TWO FROM
WAUSAU TO OSHKOSH. THE REST OF THE AREA SHOULD SEE INCREASING
CLOUDS. LOWS RANGING FROM THE UPPER TEENS NORTHEAST TO THE MIDDLE
20S SOUTH.
MONDAY...ANY PRECIP WILL HAVE EXITED CENTRAL WISCONSIN BY THE START
OF THE MORNING BUT CLOUDS WILL TAKE MUCH LONGER TO THIN AS CENTRAL
WISCONSIN WILL BE ON THE NORTHEAST EDGE OF THE BAROCLINIC ZONE.
NORTHEAST WISCONSIN WILL HAVE A MUCH GREATER CHANCE OF CLEARING
DURING THE AFTERNOON. THE COMBINATION OF CLOUDS AND AN EAST WIND
WILL KEEP MAX TEMPS COOL. HIGHS WILL BE RANGING THROUGH THE 30S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 244 PM CDT SUN MAR 22 2015
MAIN CONCERN FOR THIS PACKAGE WILL BE THE SYSTEM TUESDAY NIGHT
AND WEDNESDAY...THEN BELOW NORMAL TEMPERATURES FOR THE END OF
THE WORK WEEK INTO NEXT WEEKEND.
12Z MODELS CONTINUE TO SHOW SIGNIFICANT SYSTEM MOVING ACROSS THE
REGION TUESDAY NIGHT INTO WEDNESDAY. MANY ISSUES TO CONTEND WITH
PRECIPITATION TYPE DUE TO DRY AND COLD EASTERLY FLOW WITH LOW
DEW POINTS TUESDAY AFTERNOON...THEN WARM LAYER ALOFT TUESDAY NIGHT
INTO WEDNESDAY. ONE THING IS FOR SURE...PLENTY OF DRY AIR IN THE
LOW LEVELS TO OVERCOME AS NUMERICAL GUIDANCE INDICATING DEW POINTS
IN THE TEENS TO LOWER 20S. ALOFT...MODELS DIFFER ON HOW FAR NORTH
WARM LAYER WILL GET ON INCREASING SOUTHEAST TO SOUTH WINDS. ALSO...
ANOTHER FACTOR THAT MAY IMPACT PRECIPITATION TYPES WILL BE THE
STEEP MID LEVEL LAPSE RATES (700-500MB) AROUND 6.5 C/KM. EVEN THE
WARM LOCATIONS ACROSS EAST CENTRAL WISCONSIN COULD SEE A MIX OR
START AS SNOW UNTIL WARMER AND MORE MOIST AIR ARRIVES. THESE
ISSUES WILL HAVE AN IMPACT ON SNOW TOTALS...BUT FEEL CONFIDENT THAT
AN ACCUMULATING SNOW WILL OCCUR ACROSS THE NORTH.
PRECIPITATION WILL LINGER INTO WEDNESDAY AS SYSTEM DEPARTS THE REGION.
AN UPPER TROUGH MOVING ACROSS THE REGION WILL BRING A CHANCE OF
RAIN OR SNOW WEDNESDAY NIGHT AND THURSDAY. MAINLY DRY CONDITIONS ARE
EXPECTED INTO SATURDAY THE NEXT CHANCE OF RAIN AND SNOW IS EXPECTED
SATURDAY NIGHT AND SUNDAY.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 511 PM CDT SUN MAR 22 2015
AN UPPER DISTURBANCE WILL TRACK SOUTHWEST OF THE AREA TONIGHT.
A NARROW NORTHWEST TO SOUTHEAST BAND OF SNOW WILL EXTEND FROM
CENTRAL MINNESOTA TO FAR SOUTHWEST WISCONSIN TO NORTHERN ILLINOIS.
SOME MVFR CIGS WITH LIGHT SNOW MAY WORK INTO PARTS OF CENTRAL
WISCONSIN OR SOUTH OF LINE FROM MFI TO Y50 FOR AT TIME
TONIGHT...OTHERWISE VFR CONDITIONS EXPECTED TONIGHT INTO MONDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........TDH
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
526 PM CDT SAT MAR 21 2015
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW CANADIAN
HIGH PRESSURE BUILDING SOUTHEAST ACROSS THE NORTHERN MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES REGION. CLOUDS OFF LAKE SUPERIOR ARE
RETREATING EARLY THIS AFTERNOON AS DRY AIR ALOFT MIXES DOWN.
MEANWHILE...A WIDE SWATH OF MID-CLOUDS IN A
CONFLUENT/FRONTOGENETICAL AREA IS STREAMING SOUTHEAST OVER THE
NORTHERN PLAINS AND POISED TO ARRIVE LATER TODAY. CLOUD TRENDS AND
TEMPS ARE THE MAIN FORECAST CONCERNS OVER THE NEXT 24 HOURS.
TONIGHT...CANADIAN HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS
THE STATE OF WISCONSIN. DESPITE THE INCOMING SURFACE HIGH...LAKE
CLOUDS MAY LINGER OVER THE DOOR PENINSULA AS A RESULT OF WINDS
TURNING TO THE EAST AND 925MB TEMPS AROUND -11C. LIGHT NORTHERLY
FLOW AND INCREASING INSTABILITY MAY ALSO BRING LAKE CLOUDS INTO
VILAS COUNTY LATE TONIGHT. OTHERWISE WILL SEE 700MB CONVERGENCE
BRING IN A BAND OF MID-CLOUD ACROSS MUCH OF THE AREA. EDGE THE
NORTHERN EXTENT OF THESE CLOUDS SLIGHTLY FURTHER NORTH BASED ON THE
LATEST GUIDANCE AND SATELLITE TRENDS...AND CONSEQUENTLY...RAISED MIN
TEMPS SLIGHTLY FARTHER NORTH AS WELL. LOWS RANGING FROM THE SINGLE
DIGITS AT LAND O LAKES TO THE MIDDLE 20S SOUTH.
SUNDAY...THE MID-LEVEL CONVERGENCE ZONE WILL SINK SLIGHTLY SOUTH
THROUGH THE DAY WHICH SHOULD LEAD TO CLEARING OVER NORTHEAST
WISCONSIN. ANY LOW CLOUDS OVER N-C WISCONSIN SHOULD MIX OUT WITH
DAYTIME HEATING BY MIDDAY. THEN WILL BE WATCHING AN INVERTED
TROUGH/SHORTWAVE MOVE EAST ACROSS THE NORTHERN MISSISSIPPI VALLEY
DURING THE AFTERNOON. AHEAD OF THESE FEATURES...A BAND OF LIGHT
PRECIP WILL BE DEVELOPING AS IT PUSHES EAST ACROSS CENTRAL MINNESOTA
AND WESTERN WISCONSIN. MOST GUIDANCE INCLUDING THE NAM/SREF/AND
MESOMODELS KEEP PRECIP SOUTHWEST OF THE FORECAST AREA AND THAT
PLACEMENT COINCIDES BETTER WITH THE FRONTOGENETICAL FORCING.
NORTHEAST WINDS WILL KEEP HIGHS COOL AND WILL GO WITH MAX TEMPS
MAINLY IN THE MID TO UPPER 30S.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
MAIN CONCERN FOR THIS PERIOD WILL BE SYSTEM SUNDAY NIGHT...A
SECOND SYSTEM TUESDAY NIGHT INTO WEDNESDAY AND BELOW NORMAL
TEMPERATURES FOR THE LATTER HALF OF NEXT WEEK INTO NEXT WEEKEND.
SYSTEM FOR SUNDAY NIGHT APPEARS TO BE LOCKED IN NOW...WITH CHANCES
OF LIGHT SNOW SOUTH OF A KEWAUNEE TO TOMAHAWK LINE. WILL BE FAIRLY
SHARP GRADIENT IN THE SNOW CHANCES WITH THE HIGHEST CHANCES ACROSS
CENTRAL WISCONSIN. SNOWFALL AMOUNTS ACROSS PORTIONS OF PORTAGE...
WOOD..AND WAUSHARA COUNTIES COULD BE AROUND AN INCH. ONLY SNOW
FLURRIES WILL BE SEEN AT GREEN BAY.
EXCEPT FOR A FEW LINGERING FLURRIES MONDAY MORNING ACROSS THE
FAR SOUTH...DRY CONDITIONS WILL PREVAIL MONDAY AFTERNOON INTO
MONDAY EVENING. LATEST DEVELOP TODAY IS THAT SOME OF THE MODELS
ARE PRODUCING LIGHT PRECIPITATION AMOUNTS ACROSS THE NORTH WITH
RETURN FLOW. DID ADD SOME FLURRIES LATE MONDAY NIGHT TO ACCOUNT
FOR THIS SCENARIO.
MAIN SYSTEM STILL ON TRACK FOR TUESDAY NIGHT AND WEDNESDAY.
BOUNDARY/850MB TEMPERATURES STILL PROBLEMATIC WITH PRECIPITATION
TYPES AND SNOW AMOUNTS. ALTHOUGH NOT IN THE FORECAST...COULD BE
A LITTLE SLEET OR FREEZING RAIN MIXED IN AT TIMES ACROSS THE NORTH.
WITH SUCH UNCERTAINTIES IN THE FORECAST...DID NOT ADD TO THE FORECAST
AT THIS TIME. SOME LINGERING LIGHT RAIN OR SNOW SHOWERS COULD LINGER
INTO THURSDAY WITH COLD CYCLONIC FLOW ALOFT.
WESTERN RIDGE WILL BUILD BY THE END OF NEXT WEEK...WHICH WILL LEAD
TO BELOW NORMAL TEMPERATURES INTO NEXT WEEKEND.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 525 PM CDT SAT MAR 21 2015
MAINLY A VFR MID LEVEL CIG WILL INCREASE OVER THE AREA TONIGHT.
MID LEVEL VFR CIGS MAY LINGER OVER PARTS OF CENTRAL WISCONSIN
ON SUNDAY WHILE VFR CIGS WILL LIFT TO HIGH LEVEL CLOUDS
ELSEWHERE.
ON THE MESOSCALE LEVEL...CONVERGENCE ALONG THE LAKE MICHIGAN BREEZE
AND ONSHORE OF THE SHORELINE COUNTIES PRODUCING VERY ISOLATED
MVFR CIGS THROUGH LATE AFTERNOON AND MAY LINGER EARLY EVENING
BEFORE DISSIPATING. THE DISSIPATING OCCURRING DUE TO THE LOSS OF
THE MIXING OF THE WEST TO NORTH WINDS ALOFT AT SUNSET AND LAKE
EFFECT WIND SHIFT MOVING INLAND. PRESENT MOVEMENT SUGGESTS
REACHING GRB AROUND 7 PM...AND ATW BETWEEN 7 AND 8 PM.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW CANADIAN
HIGH PRESSURE BUILDING SOUTHEAST ACROSS THE NORTHERN MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES REGION. CLOUDS OFF LAKE SUPERIOR ARE
RETREATING EARLY THIS AFTERNOON AS DRY AIR ALOFT MIXES DOWN.
MEANWHILE...A WIDE SWATH OF MID-CLOUDS IN A
CONFLUENT/FRONTOGENETICAL AREA IS STREAMING SOUTHEAST OVER THE
NORTHERN PLAINS AND POISED TO ARRIVE LATER TODAY. CLOUD TRENDS AND
TEMPS ARE THE MAIN FORECAST CONCERNS OVER THE NEXT 24 HOURS.
TONIGHT...CANADIAN HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS
THE STATE OF WISCONSIN. DESPITE THE INCOMING SURFACE HIGH...LAKE
CLOUDS MAY LINGER OVER THE DOOR PENINSULA AS A RESULT OF WINDS
TURNING TO THE EAST AND 925MB TEMPS AROUND -11C. LIGHT NORTHERLY
FLOW AND INCREASING INSTABILITY MAY ALSO BRING LAKE CLOUDS INTO
VILAS COUNTY LATE TONIGHT. OTHERWISE WILL SEE 700MB CONVERGENCE
BRING IN A BAND OF MID-CLOUD ACROSS MUCH OF THE AREA. EDGE THE
NORTHERN EXTENT OF THESE CLOUDS SLIGHTLY FURTHER NORTH BASED ON THE
LATEST GUIDANCE AND SATELLITE TRENDS...AND CONSEQUENTLY...RAISED MIN
TEMPS SLIGHTLY FARTHER NORTH AS WELL. LOWS RANGING FROM THE SINGLE
DIGITS AT LAND O LAKES TO THE MIDDLE 20S SOUTH.
SUNDAY...THE MID-LEVEL CONVERGENCE ZONE WILL SINK SLIGHTLY SOUTH
THROUGH THE DAY WHICH SHOULD LEAD TO CLEARING OVER NORTHEAST
WISCONSIN. ANY LOW CLOUDS OVER N-C WISCONSIN SHOULD MIX OUT WITH
DAYTIME HEATING BY MIDDAY. THEN WILL BE WATCHING AN INVERTED
TROUGH/SHORTWAVE MOVE EAST ACROSS THE NORTHERN MISSISSIPPI VALLEY
DURING THE AFTERNOON. AHEAD OF THESE FEATURES...A BAND OF LIGHT
PRECIP WILL BE DEVELOPING AS IT PUSHES EAST ACROSS CENTRAL MINNESOTA
AND WESTERN WISCONSIN. MOST GUIDANCE INCLUDING THE NAM/SREF/AND
MESOMODELS KEEP PRECIP SOUTHWEST OF THE FORECAST AREA AND THAT
PLACEMENT COINCIDES BETTER WITH THE FRONTOGENETICAL FORCING.
NORTHEAST WINDS WILL KEEP HIGHS COOL AND WILL GO WITH MAX TEMPS
MAINLY IN THE MID TO UPPER 30S.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
MAIN CONCERN FOR THIS PERIOD WILL BE SYSTEM SUNDAY NIGHT...A
SECOND SYSTEM TUESDAY NIGHT INTO WEDNESDAY AND BELOW NORMAL
TEMPERATURES FOR THE LATTER HALF OF NEXT WEEK INTO NEXT WEEKEND.
SYSTEM FOR SUNDAY NIGHT APPEARS TO BE LOCKED IN NOW...WITH CHANCES
OF LIGHT SNOW SOUTH OF A KEWAUNEE TO TOMAHAWK LINE. WILL BE FAIRLY
SHARP GRADIENT IN THE SNOW CHANCES WITH THE HIGHEST CHANCES ACROSS
CENTRAL WISCONSIN. SNOWFALL AMOUNTS ACROSS PORTIONS OF PORTAGE...
WOOD..AND WAUSHARA COUNTIES COULD BE AROUND AN INCH. ONLY SNOW
FLURRIES WILL BE SEEN AT GREEN BAY.
EXCEPT FOR A FEW LINGERING FLURRIES MONDAY MORNING ACROSS THE
FAR SOUTH...DRY CONDITIONS WILL PREVAIL MONDAY AFTERNOON INTO
MONDAY EVENING. LATEST DEVELOP TODAY IS THAT SOME OF THE MODELS
ARE PRODUCING LIGHT PRECIPITATION AMOUNTS ACROSS THE NORTH WITH
RETURN FLOW. DID ADD SOME FLURRIES LATE MONDAY NIGHT TO ACCOUNT
FOR THIS SCENARIO.
MAIN SYSTEM STILL ON TRACK FOR TUESDAY NIGHT AND WEDNESDAY.
BOUNDARY/850MB TEMPERATURES STILL PROBLEMATIC WITH PRECIPITATION
TYPES AND SNOW AMOUNTS. ALTHOUGH NOT IN THE FORECAST...COULD BE
A LITTLE SLEET OR FREEZING RAIN MIXED IN AT TIMES ACROSS THE NORTH.
WITH SUCH UNCERTAINTIES IN THE FORECAST...DID NOT ADD TO THE FORECAST
AT THIS TIME. SOME LINGERING LIGHT RAIN OR SNOW SHOWERS COULD LINGER
INTO THURSDAY WITH COLD CYCLONIC FLOW ALOFT.
WESTERN RIDGE WILL BUILD BY THE END OF NEXT WEEK...WHICH WILL LEAD
TO BELOW NORMAL TEMPERATURES INTO NEXT WEEKEND.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1237 PM CDT SAT MAR 21 2015
SPOTTY MVFR CIGS OVER FAR NORTH-CENTRAL AND NORTHEAST WISCONSIN WILL
LIFT TO VFR EARLY THIS AFTERNOON AS DRIER AIR IS MIXED DOWNWARD.
THEN WILL SEE AN AREA OF MID-CLOUDS FROM THE NORTHERN PLAINS MOVE
INTO THE REGION THIS EVENING. NO PRECIPITATION IS EXPECTED THROUGH
THE END OF THE TAF PERIOD...AND DIMINISHING WINDS SHOULD LEAD TO
DECENT FLYING WEATHER TONIGHT INTO SUNDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1010 PM PDT SUN MAR 22 2015
.UPDATE...
OVERALL FORECAST REMAINS ON TRACK WITH UNSTABLE AIR MASS KEEPING
SHOWER ACTIVITY ONGOING THROUGH THIS EVENING. WE WILL MAKE A MINOR
UPDATE MAINLY TO CLEAN UP SOME OF THE EVENING WORDING.
THE COLD FRONT HAS PASSED THROUGH NORTHEAST CA AS WE HAVE
RECEIVED REPORTS OF SNOW NEAR THE LASSEN-MODOC COUNTY LINE ALONG
HIGHWAY 299, WHILE THE BOGARD WEB CAMERA IN WESTERN LASSEN COUNTY
SHOWED SNOW STARTING TO ACCUMULATE ON THE ROAD AFTER 9 PM.
CONVECTIVE ACTIVITY HAS CONTINUED ACROSS NORTHEAST CA, WITH
LIGHTNING STRIKES IN THE PAST HOUR OVER WESTERN PLUMAS AND SIERRA
COUNTIES, AND THE PRECIP BAND EXTENDING INTO EASTERN LASSEN
COUNTY. HRRR MODEL RUNS HAVE PICKED UP ON THIS PRECIP BAND, AND
WHILE SOME RAIN WILL SPREAD INTO NORTHWEST NV LATER TONIGHT, THIS
BAND IS PROJECTED TO WEAKEN BEFORE IT REACHES THE RENO AREA.
FOR THE TAHOE BASIN, PRECIP HAS DECREASED FOR THE MOMENT, BUT
MORE BANDS OF SHOWER ACTIVITY WILL DEVELOP OVERNIGHT AS THE COLD
FRONT MOVES FARTHER SOUTH. TEMPERATURES WILL COOL DOWN
SUFFICIENTLY BY EARLY MONDAY MORNING FOR SNOW TO ACCUMULATE ON
MOST AREA PASSES. A FEW INCHES OF SNOW ARE STILL EXPECTED MAINLY
ABOVE 7000 FEET, BUT SOME LIGHTER SNOW AMOUNTS REMAIN POSSIBLE
DOWN TO NEAR 6000 FEET. ENHANCED SNOWFALL RATES GREATER THAN 1
INCH PER HOUR ARE LIKELY WITH THE CONVECTIVE SNOW BANDS, ALTHOUGH
THE DURATION OF HEAVIER SNOW OVER MOST LOCATIONS WILL BE
RELATIVELY SHORT (2 HOURS OR LESS) AS THE BANDS ARE NARROW AND
MOVING QUICKLY.
FARTHER EAST, WEST WINDS GUSTING AROUND 40 MPH HAVE KICKED UP SOME
DUST AT THE LOVELOCK AIRPORT WITH VISIBILITY AS LOW AS 3/4 MILE.
THESE LOWER VISIBILITIES COULD CONTINUE AT TIMES UNTIL MIDNIGHT,
AFFECTING TRAVEL CONDITIONS ON I-80 BETWEEN LOVELOCK AND
WINNEMUCCA. WHILE THESE WINDS SHOULD DECREASE OVERNIGHT, AREAS OF
BLOWING DUST WILL BE POSSIBLE IN WEST CENTRAL NV ON MONDAY AS
WEST WINDS INCREASE AGAIN BY LATE MORNING. MJD
&&
.PREVIOUS DISCUSSION... /ISSUED 228 PM PDT SUN MAR 22 2015/
SYNOPSIS...
A PACIFIC STORM WILL BRING BREEZY WINDS ALONG WITH RAIN AND SNOW
SHOWERS INTO MONDAY. HIGH ELEVATION PASSES WILL LIKELY BE SNOW
COVERED MONDAY MORNING FROM THE TAHOE BASIN NORTHWARD. A FEW
SHOWERS WILL CONTINUE NEAR THE OREGON BORDER INTO TUESDAY. THEN
HIGH PRESSURE WILL BUILD OVER CALIFORNIA LATE IN THE WEEK WITH DRY
CONDITIONS AND TEMPERATURES BACK WELL ABOVE AVERAGE.
SHORT TERM...
MAIN FEATURE OF INTEREST WILL CONTINUE TO BE THE TROUGH ALONG 130W
THAT IS NEARING THE COAST. AS IS TYPICAL FOR EARLY SPRING SYSTEMS,
MOST OF THE MOISTURE WILL BE POST-FRONTAL AND SOMEWHAT LIMITED
COMPARED TO WHAT WE WOULD NORMALLY SEE IN MID-WINTER.
MODELS/ENSEMBLES IN GOOD AGREEMENT WITH TIMING AND TRACK OF THE
SYSTEM TONIGHT INTO TOMORROW.
BREEZY WINDS WILL CONTINUE THIS EVENING AHEAD OF THE COLD FRONT
ACROSS MUCH OF THE AREA. HOWEVER, AS HAS BEEN THE TREND WITH
PREVIOUS RUNS, THEY ARE WEAKER THAN PREVIOUSLY ADVERTISED. THIS
HAS CERTAINLY BEEN THE CASE SO FAR WITH PEAK GUSTS ONLY TO 35 MPH
IN WIND PRONE AREAS. THE WINDS WILL BE STRONGEST IN THOSE WIND
PRONE AREAS TONIGHT WITH GUSTS TO 45 MPH WHILE RIDGES COULD GUST
TO 75 MPH.
AS FOR THE PRECIP NEAR AND BEHIND THE COLD FRONT, IT WILL BE
SHORT-LIVED AND LAST 2-4 HOURS IN THE SIERRA NORTH OF TAHOE INTO
WESTERN LASSEN COUNTY. AROUND 1/2 INCH OF PRECIP POSSIBLE IN THOSE
AREAS WITH SOME LIMITED SPILLOVER INTO WESTERN NEVADA NORTH OF
I-80 WITH UP TO A TENTH OF AN INCH. SNOW LEVELS WILL START NEAR
6500-7000 THEN LOWER 1000 FEET OVERNIGHT. EXPECT SOME LIGHT
ACCUMULATIONS OVER THE SIERRA PASSES TONIGHT WHICH MAY CREATE SOME
SLICK ROADS. SNOW WILL REACH LAKE LEVEL AROUND TAHOE OVERNIGHT,
BUT LIMITED ACCUMULATIONS ON ROADS THAT LOW ALTHOUGH A FEW SPOTS
MAY SEE AN INCH OR SO OF SLUSH.
THE MAIN BAND OF PRECIP QUICKLY EXITS MONDAY MORNING WITH SOME
LINGERING SHOWERS INTO MONDAY AFTERNOON. INSTABILITY IS WEAK IT IS
APPEARS THE BEST CHANCES WILL BE IN THE SIERRA WITH ISOLATED
SHOWERS AT BEST INTO WRN NEVADA NORTH OF HIGHWAY 50.
THE JET STREAM THEN LINGERS NEAR THE OREGON BORDER INTO TUESDAY
WITH SOME WEAK WARM AIR ADVECTION. THERE IS ENOUGH MOISTURE IN THE
FLOW FOR A CHANCE OF LIGHT RAIN AT LEAST NORTH OF SUSANVILLE-
GERLACH. FURTHER SOUTH, JUST EXPECT CONTINUED MID AND HIGH CLOUDS.
THEN THE RIDGE STARTS TO BUILD IN WEDNESDAY WITH SOME WARMING,
ALTHOUGH CURRENTLY EXPECT THE GREATEST AMOUNT OF WARMING LATER IN
THE WEEK. WALLMANN
LONG TERM...THURSDAY THROUGH SUNDAY...
HIGH PRESSURE CONTINUES TO BE THE DOMINANT WEATHER FEATURE FOR THE
LONG TERM FORECAST. THEREFORE ONLY MINOR ADJUSTMENTS WERE REQUIRED
TO ACCOUNT FOR MOST RECENT MODEL VARIATIONS. TEMPERATURES ARE
STILL TRENDING WARMER THROUGH AT LEAST FRIDAY AND LIKELY STALLING
SATURDAY AS THE RIDGE BEGINS TO SHIFT EASTWARD. EXPECTING HIGHS TO
RISE INTO THE MID 70S IN WESTERN NEVADA BY FRIDAY AND UPPER 60S
FOR SIERRA VALLEYS.
AS EXPECTED, SUBSEQUENT MODEL RUNS FROM PREVIOUS DAYS CONTINUE TO
DELAY THE BREAK DOWN OF THE RIDGE. AS A RESULT, MODEL DEPICTIONS
OF LOW PRESSURE HAVE BEEN SLOWER TO MOVE INTO THE BACKSIDE OF THE
RIDGE, OFFSET BY 12 TO 24 HOURS FROM YESTERDAY`S FORECAST. SINCE
UNCERTAINTY REMAINS HIGH DUE TO THERE BEING A LITTLE MORE ROOM TO
DELAY LOW PRESSURE, FORECASTER CONFIDENCE FOR LATE SATURDAY INTO
NEXT SUNDAY REMAINS LOW. FOR NOW, CLOUD COVER SHOULD BEGIN TO
INCREASE SATURDAY AS LOW PRESSURE BEGINS TO MOVE INTO THE BACKSIDE
OF THE RIDGE. ADDED A SLIGHT CHANCE OF SHOWERS FOR SUNDAY NIGHT
WHEN THE STRONGEST ENERGY BEGINS TO MOVE INTO THE SIERRA. IF THE
LATEST RUNS VERIFY, SOME THUNDERSTORM ACTIVITY WOULD NOT BE OUT OF
THE QUESTION. BOYD
AVIATION...
CONDITIONS HAVE BECOME BREEZY ACROSS THE SIERRA INTO WESTERN
NEVADA THIS AFTERNOON. TERMINAL GUSTS HAVE GENERALLY BEEN IN THE
MID/UPPER 20S WITH LOCAL GUSTS TO 30 KTS. WINDS HAVE ALSO BEEN
MOSTLY SOUTHWEST WITH THE EXCEPTION OF KRNO AND KTVL WHERE THEY
HAVE BEEN OUT OF THE SOUTH. EXPECT WINDS TO REMAIN BREEZY
OVERNIGHT AND SHIFT MORE WESTWARD BY 14Z. MECHANICAL TURBULENCE
FOR AIRCRAFT OVER AND TO THE LEE OF THE SIERRA CONTINUES TO BE THE
MAIN CONCERN AS RIDGE GUSTS INCREASE FROM 50 KTS THIS AFTERNOON TO
OVER 65 KTS THIS EVENING AND OVERNIGHT.
OTHERWISE, VFR CONDITIONS WILL DEGRADE THIS EVENING WHEN THE NEXT
SYSTEM PUSHES INTO THE SIERRA. SOME MVFR AND OCCASIONAL IFR
CONDITIONS CAN BE EXPECTED FOR SIERRA TERMINALS DURING PERIODS OF
RAIN AND SNOW. RUNWAYS MAY BECOME INTERMITTENTLY SLICK AS BURSTS
OF SNOW ALLOW FOR BRIEF ACCUMULATION. THESE ACCUMULATIONS SHOULD
QUICKLY MELT LEAVING KTRK/KTVL WET AS GROUND TEMPERATURES REMAIN
RELATIVELY WARM.
CONDITIONS BEGIN TO IMPROVE MONDAY AFTERNOON AS LOW PRESSURE EXITS
INTO THE ROCKIES; WINDS WILL SLOW MONDAY NIGHT INTO TUESDAY. THE
REST OF THE WEEK WILL BE CHARACTERIZED BY HIGH PRESSURE AND A
WARMING TREND AS TEMPERATURES CLIMB INTO THE MID 70S. BOYD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY FROM 7 AM TO 7 PM PDT MONDAY FOR PYRAMID LAKE
IN NVZ004.
LAKE WIND ADVISORY UNTIL 11 AM PDT MONDAY FOR LAKE TAHOE IN
NVZ002.
CA...LAKE WIND ADVISORY UNTIL 11 AM PDT MONDAY FOR LAKE TAHOE IN
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS MIAMI FL
422 AM EDT MON MAR 23 2015
.DISCUSSION...
A SURFACE LOW CONTINUES TO DEVELOP ALONG THE FLORIDA PANHANDLE
WITH THE TRAILING COLD FRONT ENTERING THE CENTRAL TO EASTERN GULF.
THE GLOBAL MODEL CONSENSUS CONTINUES TO BRING THIS SYSTEM TO THE
EAST TODAY WITH THE FRONT EXPECTED TO APPROACH SOUTH FLORIDA
AROUND 00Z THIS EVENING THEN ACROSS SOUTH FLORIDA AND ADJACENT
WATERS TONIGHT AND STALL ACROSS THE SOUTHERN TIP OF THE PENINSULA
OR FLORIDA STRAITS TUESDAY MORNING.
FOR TODAY...AS THE AFOREMENTIONED FRONT CONTINUES TO PASS ACROSS
THE EASTERN GULF TODAY CHANCES OF SHOWERS AHEAD OF THE FRONT WILL
CONTINUE THROUGH THE MORNING HOURS INTO THE AFTERNOON...WHEN THE
GREATEST COVERAGE OF SHOWERS IS EXPECTED. THUS FAR SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON...WITH A GENERAL CONSENSUS OF THE GLOBAL MODELS AND SHORT
RANGE ENSEMBLE ALTHOUGH THE HRRR MODEL INDICATES LESS COVERAGE AND
IS SLOWER IN SHOWER DEVELOPMENT. ONLY ISOLATED THUNDERSTORM
ACTIVITY IS FORECAST THIS AFTERNOON WITH THE GUIDANCE CONTINUING
TO SUGGEST THAT MID LEVEL TEMPERATURES...LAPSE RATES AND
INSTABILITY IS NOT SUFFICIENT TO SUPPORT ORGANIZED CONVECTION.
HOWEVER THE GUIDANCE DOES INDICATE THAT THE DEEPER LAYERED
MOISTURE AHEAD OF THE FRONT MAY NOT REACH THE PENINSULA UNTIL THE
AFTERNOON HOURS AND SUFFICIENT DAY TIME HEATING COULD TRIGGER SOME
ISOLATED THUNDERSTORMS. THE FORECAST LOW LEVEL WIND PROFILE INDICATES
A PROFILE SUPPORTIVE OF GUSTY WINDS WITH ANY THUNDERSTORM ACTIVITY
BUT IS NOT EXPECTED TO BE BE AN OVERALL THREAT WITH LOW LEVEL
SHEAR NOT SIGNIFICANT. LASTLY...WITH SOUTHWESTERLY WINDS EXPECTED
ACROSS THE PENINSULA THE EAST COAST SEA BREEZE SHOULD BE
SUPPRESSED THIS AFTERNOON...BUT JUST ALONG THE IMMEDIATE COAST IF
THE WINDS BECOME SOUTHEASTERLY THEN THE LOW LEVEL WIND PROFILE
MIGHT SUPPORT A SHORT LIVED FUNNEL CLOUD BUT CONFIDENCE IS LOW.
FOR TUESDAY...THE BOUNDARY AND ASSOCIATED MOISTURE IS FORECAST TO
STALL ACROSS THE FLORIDA STRAITS OR SOUTHERN TIP OF THE PENINSULA
WITH SOME ISOLATED SHOWERS POSSIBLE BUT MAINLY EXPECTED ACROSS THE
ATLANTIC WATERS.
FOR WEDNESDAY THROUGH FRIDAY...BY WEDNESDAY THE SURFACE AND LOW
LEVEL WINDS ARE FORECAST TO BECOME MORE SOUTHERLY WITH THE
BOUNDARY AND ASSOCIATED MOISTURE LIFTING NORTHWARD WITH MAINLY
AFTERNOON SHOWERS FORECAST THROUGH THIS PERIOD.
FOR THE EXTENDED FORECAST...FOR SEVERAL DAYS A STRONG COLD FRONT
HAS BEEN FORECAST TO AFFECT THE REGION THIS UPCOMING WEEKEND WITH
THE GLOBAL MODELS CONTINUING TO FORECAST THIS SCENARIO.
HOWEVER...WHILE THERE IS STILL GENERAL CONSENSUS THE TIMING OF THE
FRONTAL PASSAGE HAS BEEN SLOWED DOWN AND IS NOW FORECAST TO PASS
ACROSS SOUTH FLORIDA AND REGIONAL WATERS ON SATURDAY THEN EXIT THE
REGION SUNDAY NIGHT...ALMOST A 24 HOUR DIFFERENCE FROM PREVIOUS
GUIDANCE. EXTENDED GUIDANCE INDICATES HIGHS ON SUNDAY ONLY IN THE
LOWER 70S...WILL HAVE TO WAIT AND SEE HOW THIS SCENARIO CHANGES IN
FUTURE GUIDANCE.
&&
.MARINE...
ISOLATED THUNDERSTORMS ARE FORECAST ACROSS THE REGIONAL WATERS FOR
THIS AFTERNOON AND EARLY EVENING HOURS. IN GENERAL WINDS FORECAST
TO BE 15 KNOTS OR LESS THROUGH MID-WEEK WITH SEAS REMAINING WELL
BELOW ADVISORY LEVELS. WITH THE FORECAST PASSAGE OF A STRONG COLD
FRONT THIS UPCOMING WEEKEND SEAS COULD REACH NEAR ADVISORY
LEVELS...BUT TIMING IS DIFFICULT WITH VARYING GUIDANCE AND WILL
HAVE TO WAIT FOR FURTHER GUIDANCE CONSENSUS FOR TIMING PURPOSES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 85 69 87 70 / 40 30 10 10
FORT LAUDERDALE 85 71 84 71 / 30 20 10 10
MIAMI 86 71 87 71 / 30 20 10 10
NAPLES 83 69 84 67 / 40 20 10 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
415 AM EDT MON MAR 23 2015
.DISCUSSION...
...INCREASED RAIN CHANCES TODAY WITH A SLIGHT CHANCE OF STORMS...
CURRENTLY-TODAY...A WEAK LOW PRESSURE WAVE IS FORECAST TO SLIDE
EAST ALONG A FRONTAL BOUNDARY JUST NORTH OF THE REGION. A BAND OF
PRE FRONTAL CONVECTION HAS BEEN INCREASING IN THE EASTERN GULF OF
MEXICO AND STARTING TO PUSH INLAND RECENTLY. THE HRRR SHOWS THIS
BAND OF CONVECTION PUSHING EAST AROUND 20 MPH ACROSS OUR
NORTH/CENTRAL SECTIONS THROUGH MIDDAY AND ACROSS THE SOUTH THIS
AFTERNOON. QUITE HIGH PRECIPITABLE WATER VALUES TO AROUND 1.75
INCHES POINT TO LIKELY POPS FOR MOST OF THE AREA.
DEEP LAYER SHEAR WILL BE RATHER STRONG AS A SHORTWAVE TROUGH AND
ACCOMPANYING JET STREAK APPROACH...BUT WITH THE PRE FRONTAL BAND
OF CONVECTION PUSHING ACROSS THE NORTH HALF EARLY...THERE WILL BE
LIMITED HEATING/INSTABILITY. SOUTHERN SECTIONS WILL HAVE MORE TIME
TO HEAT UP...REACHING THE LOWER-MID 80S...SO A FEW STRONG STORMS
COULD OCCUR THERE.
THE FRONTAL BOUNDARY WILL SLOWLY SAG TOWARDS OUR NORTHERN AREAS
THIS AFTERNOON...AND ADDITIONAL DEVELOPMENT IS POSSIBLE THEN
ACROSS THE NORTHERN HALF...DEPENDING ON HOW MUCH THE ATMOSPHERE
CAN RECOVER BEHIND THE INITIAL BAND OF CONVECTION.
SHOWERS AND ISOLATED STORMS WILL BE RATHER QUICK MOVING...BUT
SOME BENEFICIAL RAINFALL AMOUNTS OF A QUARTER TO HALF INCH ARE
EXPECTED. LOCALLY HIGHER TOTALS ARE POSSIBLE WITH THE STRONGER
CELLS.
TONIGHT...THE VERY WEAK FRONTAL BOUNDARY IS PROGGED TO SAG INTO
THE CENTRAL PENINSULA. WITH A WEAK VORT LOBE MOVING THROUGH...LOW
POPS LOOK REASONABLE THROUGH EVENING. A WEAK BOUNDARY AND HIGH
AMOUNTS OF LOW LEVEL MOISTURE USUALLY POINT TO LATE NIGHT FOG AND
WILL CONTINUE TO CARRY THAT IN THE FORECAST.
TUE-WED...
STRONG ZONAL COMPONENT TO THE REGIONAL MID/UPR LVL WIND PATTERN WILL
PUSH THE POST FRONTAL RIDGE OVER THE SRN PLAINS ACRS THE DEEP SOUTH
ON TUE...THEN OFF THE SERN SEABOARD TUE NIGHT. THERE...IT WILL
BRIDGE THE FRONTAL TROF IN THE VCNTY OF THE BAHAMA BANK BEFORE
MERGING WITH LARGER RIDGE BUILDS INTO OVER THE MID ATLC/NEW ENGLAND
STATES. TRACK OF THE RIDGE WILL GENERATE A SHALLOW E/NE FLOW ACRS
CENTRAL FL ON TUE THAT WILL VEER TO THE S ON WED WHILE
SIMULTANEOUSLY PULLING STABLE MID LVL AIR ACRS THE STATE.
GFS INDICATES THERMAL RIDGING IN THE H85-H70 LYR THRU MID WEEK...IN
LINE WITH THE LAPSE RATES ASSOCD WITH THE POST FRONTAL AIRMASS:
RUC40 SHOWING H85-H70 LAPSE RATES AOB 5.0C/KM ACRS E TX AND THE LWR
MS VALLEY...VALUES AS LOW AS 2.5C/KM OVER THE NE GOMEX. RUC ALSO
SHOWING LITTLE IN THE WAY OF MID LVL VORTICITY OVER THE THE REGION
OUTSIDE OF THE IMMEDIATE VCNTY OF THE FRONTAL TROF...LITTLE CHANGE
EXPECTED AS HI PRES BUILDS OVER THE SW ATLC AND BLOCKS OUT ANY SHORT
WAVE ENERGY FROM PUSHING INTO CENTRAL FL. ZONAL JET OVER THE DEEP
SOUTH WILL NOT BE ABLE TO ADD ANY SIG UPR LVL DIVERGENCE TO THE
EQUATION EITHER.
LIMITED MOISTURE ON TUE WILL INCREASE SLOWLY THRU WED AS LOW LVL
WINDS SHIFT TO THE S AND BEGIN TO TAP TROPICAL AIR. HOWEVER...THE
DRY/STABLE POST FRONTAL AIR WILL TAKE TIME TO MODIFY SUFFICIENTLY TO
SUPPORT ANYTHING MORE THAN SLGT CHC POPS...MOST OF WHICH WILL BE
CONFINED TO THE COASTAL/SRN COUNTIES. NE WINDS TUE WILL KEEP MAX
TEMPS IN THE U70S/L80S ALONG THE COAST...L/M80S INLAND. SRLY WINDS
WED WILL PUSH MAX TEMPS BACK INTO THE L/M80S AREAWIDE. ONSHORE FLOW
WILL KEEP MIN TEMPS IN THE L/M60S.
THU-SUN...
GFS/ECM MODELS CONTINUE TO INDICATE THE ZONAL WIND PATTERN OVER THE
ERN CONUS WILL BCM HIGHLY AMPLIFIED THRU THE LATTER HALF OF THE WEEK
AS A 140KT JET STREAK OVER THE W PAC WORKS ITS WAY EWD. PRECIP
CHANCES INCREASE FRI AFTN AND CONT THRU SAT AS THE UPSTREAM JET
ENERGY PLOWS INTO THE WRN CONUS AND INDUCES A FULL LATITUDE FRONTAL
TROF OVER E MS RIVER VALLEY.
BOTH MODELS HAVE TRENDED SLOWER WITH THE NEXT FROPA...TIMING LOOKING
MORE TOWARD FRI NIGHT THRU SAT. WILL GO WITH LOW END PRECIP CHANGES
THRU THU AS LOW LVL RIDGE AXIS TO THE S WILL CONTINUE TO TAP
TROPICAL MOISTURE AHEAD OF THE APPROACHING FRONT. BEST RAIN CHANCES
FRI AFTN THRU SAT AFTN...DECREASING BLO MENTIONABLE LVLS SAT NIGHT
AS THE TROF PUSHES THE FRONT CLEAR OF THE FL PENINSULA. PREFRONTAL
MAX TEMPS RANGING FROM THE U70S/L80S ALONG THE COAST AND M/U80S
INTERIOR...POST FRONTAL TEMPS M60S/L70S ALONG THE COAST AND L/M70S
INTERIOR. PREFRONTAL MIN TEMPS THU NIGHT M/U60S...DROPPING INTO THE
M/U50S N OF I-4 FRI NIGHT AS THE FRONT PUSHES INTO CENTRAL FL. SAT
NIGHT NOTICABLY COOLER WITH TEMPS FALLING INTO THE L/M50 OVER MOST
OF THE CWA...A FEW SPOTS FALLING BLO 50F N OF I-4.
&&
.AVIATION...WESTERLY LOW LEVEL WINDS AHEAD OF A WEAK FRONTAL
BOUNDARY FINALLY PUSHED THE REMNANT FOG AWAY FROM THE VOLUSIA
COUNTY COAST AROUND MIDNIGHT. QUICK MOVING SHOWERS AND ISOLATED
STORMS WILL AFFECT THE TERMINALS NORTHWARD FROM KISM-KMLB THIS
MORNING...THEN SPREAD SOUTHWARD TO KVRB-KSUA DURING THE AFTERNOON.
BRIEF IFR IS POSSIBLE ALONG WITH GUSTY 30-40 MPH WINDS.
THERE IS A CHANCE FOR FOG AGAIN LATE TONIGHT AS THE WEAK FRONTAL
BOUNDARY SETTLES INTO CENTRAL FLORIDA. IT COULD BECOME DENSE SINCE
MUCH OF THE AREA WILL GET RAIN WETTED TODAY AND LOW LEVEL WINDS
WILL BECOME VERY LIGHT.
&&
.MARINE...
TODAY-TONIGHT...A MAINLY WESTERLY WIND FLOW IS FORECAST 5-10
KNOTS NEAR SHORE AND 10-15 KNOTS OFFSHORE. WINDS SHOULD DIMINISH AND
SWING AROUND TO NORTH TONIGHT FROM ABOUT THE CAPE NORTHWARD. THE
MAIN CONCERN FOR MARINERS WILL BE QUICK MOVING SHOWERS AND
ISOLATED STORMS THAT MOVE ACROSS THE WATERS THIS MORNING FROM
ABOUT MELBOURNE NORTHWARD...THEN IN THE AFTERNOON SOUTH OF THERE.
GUSTY WINDS TO 35 KNOTS WILL BE POSSIBLE ALONG WITH BRIEF
TORRENTIAL DOWNPOURS.
TUE-TUE NIGHT...HI PRES BUILDING N OF THE FL PANHANDLE WILL GENERATE
A GENTLE TO MODERATE E/NE BREEZE THRU THE DAY...BCMG A MODERATE
SE BREEZE OVERNIGHT AS THE RIDGE BUILDS OFF THE SERN SEABOARD.
SEAS 2- 4FT NEARSHORE AND 3-5FT OFFSHORE BUILDING TO 4-6FT
AREAWIDE...UP TO 7FT IN THE GULF STREAM AFT SUNSET.
WED-WED NIGHT...MODERATE TO FRESH S/SE BREEZE AS THE W ATLC RIDGE IS
REINFORCED BY A CONTINENTAL RIDGE BUILDING OFF THE MID ATLC/NEW
ENGLAND COAST. SEAS 4-6FT NEARSHORE AND 5/7FT OFFSHORE.
THU-THU NIGHT...GENTLE TO MODERATE SRLY BREEZE THRU THE DAY...BCMG
SW AFT SUNSET AS THE NEXT FRONTAL TROF PUSHES INTO THE DEEP SOUTH.
SEAS SUBSIDING TO 4-5FT NEARSHORE AND 5-6FT OFFSHORE.
FRI-FRI NIGHT...GENTLE TO MODERATE W/SW BREEZE AHEAD OF THE NEXT
COLD FRONT. WINDS VEERING TO W/NW FROM SEBASTIAN INLET NWD AS THE
FRONT PUSHES THRU CENTRAL FL. SEAS 3-4FT NEARSHORE AND 4-5FT
OFFSHORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 77 62 80 66 / 70 20 10 20
MCO 80 63 86 66 / 70 20 10 10
MLB 80 64 83 69 / 60 30 10 20
VRB 83 64 82 65 / 50 30 10 20
LEE 79 62 84 64 / 70 20 10 10
SFB 79 62 84 66 / 70 20 10 10
ORL 80 64 85 66 / 70 20 10 10
FPR 83 61 82 65 / 50 30 10 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....BRAGAW
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
355 AM EDT MON MAR 23 2015
.SHORT TERM (TODAY - TUESDAY)...
IN THE MID/UPPER LEVELS... THE HIGH PRESSURE RIDGE SOUTH OF FLORIDA
HAS WEAKENED AS A SHORT WAVE TROUGH MOVES EASTWARD ALONG THE
NORTHERN GULF COAST. THIS TROUGH COMBINED WITH DIVERGENCE ALOFT
ASSOCIATED WITH A 120 KNOT JET MAX OVER GEORGIA IS SUPPORTING
THE DEVELOPMENT OF AN ELONGATED AREA OF LOW PRESSURE FROM THE
WESTERN ATLANTIC TO THE FLORIDA PANHANDLE. A COLD FRONT EXTENDS
SOUTHWEST FROM THIS LOW AND WILL PASS OVER THE FLORIDA PENINSULA
THROUGH THE DAY. AS THIS TROUGH CLEARS THE AREA LATE MONDAY
EVENING...WEAK ZONAL FLOW WILL SETUP OVER THE SOUTHEASTERN CONUS.
ON THE SURFACE BEHIND THE FRONT...HIGH PRESSURE OVER NEW ENGLAND
WILL RIDGE SOUTHWEST ALONG THE EASTERN SEABOARD INFLUENCING THE
WEATHER FOR THE NEXT SEVERAL DAYS.
RADAR IMAGERY THIS MORNING ALREADY HAS SHOWERS STREAMING IN FROM
THE WEST MAKING LANDFALL ALONG THE NATURE COAST. THE HRRR GUIDANCE
HAS THE LEADING EDGE OF THESE RAIN BANDS MOVING INTO THE TAMPA
BAY AREA AROUND 12Z AND WILL CONTINUE MOVING SOUTHWARD REACHING
THE CHARLOTTE HARBOR AREA BETWEEN 15-18Z. WE HAVE NOT SEEN A LOT
OF LIGHTNING WITH THE FRONT...BUT WE CANT RULE OUT AN ISOLATED
THUNDERSTORM AND GUSTY WINDS AS THIS FRONT MOVES THROUGH THE AREA.
TEMPERATURES WILL REMAIN WARM...BUT WITH INCREASING CLOUD COVER AND
RAIN...IT WILL FEEL A FEW DEGREES COOLER THAT WHAT WE HAVE SEEN
OVER THE PAST SEVERAL DAYS.
&&
.MID/LONG TERM (TUESDAY NIGHT-SUNDAY)......
MODELS IN FAIR AGREEMENT WITH FAST FLAT QUASI ZONAL FLOW ALOFT
MIDWEEK. WEAK SURFACE HIGH PRESSURE BUILDS DOWN THE EASTERN SEABOARD
BRIDGING INTO THE GULF OF MEXICO WITH VEERING EAST-SOUTHERLY LOW
LEVEL FLOW FROM THE ATLANTIC BRINGING SOME MOISTURE RETURN FOR LOW
END DIURNAL POPS MAINLY OVER INLAND AREAS. WARM AND HUMID CONDITIONS
TO RETURN WITH TEMPERATURES ABOVE NORMAL.
FRIDAY...LARGE AMPLIFYING UPPER TROUGH DEEPENING INTO THE GULF
REGION. SURFACE LOW PRESSURE STORM CENTER TO MOVE THROUGH THE DEEP
SOUTH WITH ATTENDANT STRONG LATE SEASON COLD FRONT SWEEPING THROUGH
FLORIDA FRIDAY AND FRIDAY NIGHT. POPS CONTINUE TO INCREASE...NOW
INTO THE LIKELY CATEGORY AHEAD OF AND ALONG THE FRONT WHILE JET
DYNAMICS AND UPPER SUPPORT TO PRODUCE MORE WIDESPREAD TSTORMS WITH
THE SYSTEM AS WELL.
UPPER TROUGH TO SWING THROUGH THE REGION WITH NW FLOW BY SUNDAY AS
STRONG SURFACE HIGH PRESSURE TO BUILD INTO THE AREA BEHIND THE FRONT
ON BREEZY NW-N WINDS FOR THE WEEKEND WITH COOLER AND DRIER
CONDITIONS EXPECTED AND TEMPERATURES 10 PLUS DEGREES BELOW NORMAL.
&&
.AVIATION...
CONDITIONS WILL START OFF THIS MORNING AS VFR...BUT WITH THE
APPROACHING COLD FRONT...LOW/MID CLOUDS WILL MOVE INTO THE AREA AS
WELL AS RAIN SHOWERS AND ISOLATED THUNDERSTORMS TO PRODUCE PERIODS
OF MVFR CONDITIONS AFTER 12Z. WINDS WILL REMAIN OUT OF THE SOUTHWEST
BETWEEN 5 TO 10 KNOTS...BUT SOME GUSTY WINDS CAN BE EXPECTED IN THE
VICINITY OF THUNDERSTORMS. CONDITIONS WILL IMPROVE FOR THE NORTHERN
TERMINALS AFTER 21Z AND AFTER 03Z FOR THE SOUTHERN TERMINALS. VFR
CONDITIONS EXPECTED AFTER 03Z FOR ALL LOCATIONS.
&&
.MARINE...
WINDS WILL REMAIN OUT OF THE SOUTHWEST AT 10 TO 15 KNOTS OUT AHEAD
OF AN APPROACHING COLD FRONT. SHOWERS AND ISOLATED THUNDERSTORMS CAN
BE EXPECTED THROUGH THE DAY ON MONDAY...THEN CLEARING UP BY LATE
MONDAY NIGHT. WINDS WILL SHIFT TO THE NORTHEAST BEHIND THIS FRONT
AS HIGH PRESSURE TO THE NORTH RIDGES OVER THE AREA. NORTHEAST
THROUGH EAST WINDS WILL PERSIST THROUGH THE MIDDLE OF NEXT
WEEK...THEN VEERING AROUND TO THE SOUTH AHEAD OF ANOTHER FRONT THAT
WILL MOVE THROUGH THE REGION ON FRIDAY. WINDS AND SEAS ARE EXPECTED
TO REMAIN BELOW HEADLINE CRITERIA THROUGH THE WEEK.
&&
.FIRE WEATHER...
HUMIDITY LEVELS HAVE INCREASED WITH THE APPROACHING COLD FRONT AND
WILL STAY ABOVE ANY CRITICAL LEVELS FOR THE NEXT SEVERAL DAYS. WITH
LIGHT WINDS AND LOW ERC VALUES...NO FIRE WEATHER ISSUES ARE EXPECTED
AT THIS TIME. SOME PATCHY FOG WILL BE POSSIBLE EARLY THIS MORNING
AHEAD OF THE FRONT...THEN DRIER AIR SHOULD PRECLUDE FOG DEVELOPMENT
THROUGH MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 80 66 81 66 / 70 10 10 10
FMY 82 66 85 65 / 50 20 10 10
GIF 80 63 84 65 / 70 20 10 10
SRQ 79 65 80 63 / 60 10 10 0
BKV 80 59 82 59 / 70 10 10 10
SPG 80 68 81 68 / 70 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...74/WYNN
LONG TERM/DECISION SUPPORT...25/DAVIS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
120 AM CDT MON MAR 23 2015
.SHORT TERM...
308 PM CDT
THROUGH TUESDAY NIGHT...
THE FOCUS ON THE FIRST THREE DAYS OF THE FORECAST WAS
SNOW IN THE FIRST 24 HOURS AND THEN RAIN TIMING...AMOUNTS...AND
WHETHER THUNDER WILL ACCOMPANY ON TUESDAY AFTERNOON AND NIGHT. SO
IN OTHER WORDS...A CLASSIC SPRINGTIME PATTERN IN THE MIDWEST.
THE AFTERNOON REGIONAL RADAR MOSAIC INDICATES A NARROW CORRIDOR
OF REFLECTIVITY PERSISTING FROM FAR SOUTHERN MN THROUGH THE NORTH
CHICAGO METRO. TO THE IMMEDIATE NORTH OF THE IL STATE LINE AND
FURTHER NORTHWEST THIS CORRIDOR HAS FILLED IN WITH POCKETS OF
HEAVY SNOW AND ONE QUARTER MILE VISIBILITY. DESPITE THIS NEAR
PROXIMITY...THINK THAT FAR NORTHERN ILLINOIS WILL MAINLY SEE SOME
SPORADIC LIGHT SNOW THROUGH THIS EVENING. THE NORTHERN PARTS OF
WINNEBAGO...BOONE...AND INTO MCHENRY AND LAKE COUNTIES COULD GET
INTO A BRIEF SNOW BURST OR TWO...BUT ANYTHING OF THAT NATURE
SHOULD BE BRIEF AS OBSERVATIONAL TRENDS OF VISIBILITY AND DEW
POINTS INDICATE DRY AIR WILL OFFSET SOME OF THESE RATES COMING OUT
OF THE CLOUD DECK.
OF MORE CONCERN IS LATER TONIGHT AS THE LOW AMPLITUDE BUT WELL-
DEFINED SHORT WAVE TROUGH OVER SOUTH DAKOTA NEARS THE REGION. BY
OVERNIGHT THE LOW-LEVEL INFLUENCE OF THIS WILL HELP INCREASE
700-925MB MOISTURE TRANSPORT ENDING THE DRY AIR SUPPRESSION AND
LIKELY LEADING TO A BLOSSOMING OF SNOW FROM NORTHWEST TO SOUTHEAST
OVERNIGHT. THERMAL PROFILES SUPPORT SNOW FROM THE GET GO AND
ATTENTION HAS BEEN ON KEYING IN HOW PERSISTENT AND WHERE MESOSCALE
FORCING WILL INDUCE A BAND OF SNOW ON MONDAY MORNING. CONCEPTUALLY
THIS TYPE OF PACIFIC SYSTEM...WITH ALMOST A CLIPPER NATURE AS IT
COMES IN TOMORROW MORNING...WOULD HAVE A FRONTOGENETIC
ENHANCEMENT WITHIN ITS FOCUSED BUT DEEP VERTICAL MOTION. GIVEN
CURRENT OBSERVATIONAL TRENDS ALREADY ALONG THAT BAROCLINIC ZONE
WITH JUST A LEAD PERTURBATION...AND THE FORECAST OF NEGATIVE EPV
/ INSTABILITY FROM MOST GUIDANCE...THERE SHOULD BE NO PROBLEM
HAVING MODERATE SNOW DURING THE MORNING COMMUTE...WITH AN AREA OF
TEMPORARY HEAVY SNOWFALL RATES POSSIBLE. THE CHALLENGE IS KEYING
IN ON HOW FAR EAST AND SOUTH THAT HEAVIER SNOW EXTENDS AND HOW
LONG. FOR RIGHT NOW HAVE NORTH CENTRAL IL MOST FAVORED IN DURATION
BUT LIKELY AT LEAST SOME HEAVY BURSTS EXTENDING EAST INTO A PART
OF THE CHICAGO METRO.
MIXING RATIOS OF 2 TO 3 G/KG ON LIFTED LAYERS LOOK TO OFFSET NOT-
THE-BEST THERMAL PROFILE FOR EFFICIENT RATIOS. IN THE FORECAST WE
HAVE THIS SUPPORTING TOTAL SNOWFALL AMOUNTS OF 2 TO 3.5 INCHES IN
MUCH OF NORTH CENTRAL IL WHILE 1 TO 2 INCHES ACROSS MUCH OF THE
REST OF THE AREA...WITH RATES AT TIMES ENOUGH TO OFFSET THE MILD
PAVEMENT TEMPERATURES /UPPER 40S TO MID 50S/. THE EXCEPTION WOULD
BE THE FAR SOUTH WHERE RATIOS LOOK TO BE QUITE LOW AND
TEMPERATURES MONDAY MORNING SHOULD BE SEVERAL DEGREES ABOVE
FREEZING...POSSIBLY EVEN YIELDING A MIX FROM PONTIAC TO FOLWER AND
SOUTHWARD.
FOR RIGHT NOW HAVE FELT MOST COMFORTABLE GIVEN FORECAST SNOWFALL
RATES AND TOTAL SNOWFALL AMOUNTS TO ISSUE A WINTER WEATHER
ADVISORY FOR THE ROCKFORD AREA AND ADJACENT COUNTIES...WHILE
HITTING THE REMAINDER OF THE AREA WITH A SPECIAL WEATHER
STATEMENT. IT IS CERTAINLY POSSIBLE THE ADVISORY WILL NEED TO BE
EXPANDED FOR A CORRIDOR EAST-SOUTHEASTWARD GIVEN THE TIME OF DAY
WHICH SNOW WILL OCCUR...BUT OBSERVATIONAL TRENDS OF UPSTREAM
SNOWFALL RATES COMPLIMENTING FURTHER SHORT RANGE GUIDANCE...WILL
BETTER ENABLE THE EVENING SHIFT TO MAKE THAT DECISION IF
NECESSARY.
ANY PRECIPITATION BY EARLY MONDAY AFTERNOON SHOULD BECOME LIGHT
AND SHIFTING SOUTHEAST...WITH THERMAL PROFILES INDICATING THE
POSSIBILITY OF SOME LIGHT DRIZZLE/RAIN AS SATURATION IS LOST IN
THE ICE NUCLEATION LAYER.
LOOKING AHEAD TO TUESDAY INTO TUESDAY NIGHT...NCEP MODEL GUIDANCE
HAS ACTUALLY TRENDED BACK A LITTLE QUICKER WITH THE PRECIP SPREAD
INTO THE AREA TUESDAY AHEAD OF AN IMPRESSIVE WAVE...WHICH WILL
ACQUIRE A NEGATIVE TILT AS IT MOVES OVER THE AREA TUESDAY NIGHT.
CONTINUE TO EASE RAIN SHOWERS NORTHEASTWARD DURING THE DAY CLOSER
TO THE EC...BUT IF THIS TREND CONTINUES THAT MAY NEED TO BE SPED
BACK UP. THE CHANCES FOR MORE RAINFALL AND CONVECTIVE CHANCES WILL
REMAIN FOCUSED ON TUESDAY NIGHT AS THE ELEVATED LAPSE RATES
STEEPEN AND PWATS SHARPLY INCREASE. RAINFALL AMOUNTS IN EXCESS OF
ONE HALF INCH LOOK PLAUSIBLE OVER THE AREA...ESPECIALLY IF
THUNDER COVERAGE IS MORE THAN SCATTERED.
TEMPERATURES LOOK TO CONTINUE BELOW NORMAL THROUGH TUESDAY...WITH
RISING TEMPERATURES TUESDAY NIGHT.
&&
.LONG TERM...
300 PM CDT
WEDNESDAY THROUGH SUNDAY...
LONG TERM...WEDNESDAY THROUGH SATURDAY...
THE INITIAL CONCERN WILL BE STRONG SOUTHWEST WINDS AS THE STRONG LOW
MOVES FROM SOUTHERN WISCONSIN TO GEORGIAN BAY ON WEDNESDAY. LOW
INTENSITY LOOKS TO BE PEAKING WEDNESDAY MORNING WITH THE LOW JUST
NORTH OF THE CWA WITH A SLIGHT WEAKENING AS IT TRACKS ACROSS
NORTHERN LAKE MICHIGAN. THIS WILL BE A GOOD STRONG WIND SET UP
ACROSS THE AREA...ESPECIALLY NORTHERN SECTIONS. FORECAST SOUNDINGS
CONTINUE TO SHOW DIFFERENCES IN SPEEDS THROUGH THE LOWEST FEW
THOUSAND FEET OF THE ATMOSPHERE BUT EVEN THE LOWER END GUIDANCE
SHOWS 30+ KT GUST POTENTIAL STARTING EARLY WEDNESDAY MORNING. IN
ADDITION...SOME RAIN SHOWERS AND ISOLATED THUNDER MAY LINGER ACROSS
NORTHERN AREAS FIRST THING WEDNESDAY MORNING BEFORE DRIER AIR TAKES
OVER. HIGHS WILL BE QUITE A BIT WARMER WITH HIGHS IN THE 50S NORTH
AND PROBABLY 60S SOUTH. A LESS FOCUSED UPPER TROUGH WILL KICK
ANOTHER SURFACE LOW FROM THE SOUTHERN PLAINS UP THE OHIO VALLEY AND
TO NORTHERN NEW ENGLAND THURSDAY. THIS LOW WILL PASS TO THE SOUTH OF
THE AREA WEDNESDAY EVENING BRINGING SHOWER CHANCES TO THE SOUTHERN
HALF OR SO OF THE AREA. A DEEPER UPPER TROUGH WILL THEN PIVOT ACROSS
THE PLAINS AND GREAT LAKES THURSDAY BRINGING A COLD FRONT ACROSS THE
AREA THURSDAY MORNING...WITH SOME PRECIP POTENTIAL WITH THE UPPER
TROUGH PASSAGE LATER IN THE DAY. STRONG HIGH PRESSURE WILL MOVE FROM
CENTRAL CANADA TO THE CENTRAL AND SOUTHERN PLAINS INTO SATURDAY WITH
MUCH COLDER AIR RETURNING TO THE AREA. WILL PROBABLY ONLY SEE HIGHS
IN THE 30S FRIDAY AND NEAR 40 SATURDAY. LIGHT LAKE EFFECT PRECIP MAY
OCCUR ACROSS ACROSS FAR NORTHEAST ILLINOIS AND NORTHWEST INDIANA
FRIDAY.
THE LONGWAVE UPPER TROUGH WILL DEEPEN ACROSS THE EASTERN U.S. WHILE
SHARP RIDGING BUILDS WEST LATE IN THE WEEK. AN UPPER TROUGH LOOKS TO
MOVE SOUTHEAST FROM THE NORTHERN PACIFIC SHUNTING THE RIDGE EAST
INTO SUNDAY WHICH MAY BRING A WARM UP BUT WELL ORGANIZED LOW
PRESSURE IS EXPECTED TO CROSS THE AREA LATER SUNDAY ULTIMATELY
EVOLVING INTO ANOTHER DEEP LONGWAVE TROUGH OVER THE EASTERN U.S. SO
WARMING MAY END UP BEING SHORT LIVED.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* EAST TO NORTHEAST WINDS BETWEEN 10 AND 15KT THROUGH ENTIRE TAF
PERIOD. OCCASIONAL GUSTS OVERNIGHT TO 18KT.
* LGT SNOW UNTIL 10Z...INTENSITY AND COVERAGE OF SNOW PICKS UP
ARND 10-12Z AND LINGERS THROUGH 15Z.
* STEADIER SNOW WILL BRING IFR/LIFR CONDS FROM 11Z THRU 16Z.
* SNOW MAY MIX OR CHANGE TO LIGHT FREEZING DRIZZLE LATE IN THE
MORNING BEFORE ENDING SHORTLY AFT MIDDAY.
BEACHLER
//DISCUSSION...UPDATED 06Z...
REGIONAL RADAR SHOWS A NARROW CHANNEL OF LIGHT SNOW STRETCHING
FROM SOUTHWEST WISC EAST ACROSS FAR NORTHEAST IL AND OVER ORD.
EAST WINDS CONTINUE TO KEEP THE NEAR SFC VERY DRY...WHICH IS
KEEPING THE PRECIP INTENSITY VERY LIGHT AND ONLY MINOR REDUCTIONS
TO CIGS/VSBYS. GUIDANCE HAS BEEN RELATIVELY CONSISTENT WITH THE
INTENSITY INCREASING ARND 9-10Z...AND LIKELY QUICKLY BRINING
CIGS/VSBY DOWN TO ARND IFR CONDS. SHORTLY AFT 11Z THE STRONGEST
FORCING WILL ARRIVE AND MAY REDUCE VSBYS DOWN TO ARND 1/2SM AND
POSSIBLY BRIEFLY TO 1/4SM. THIS APPEARS TO IMPACT ALL OF NORTHERN
IL AND NORTHWEST IN TAF SITES THROUGH 15Z...THEN THE SLUG OF DEEP
MOISTURE QUICKLY PEELS EAST/SOUTHEAST AND QUICKLY BRINGS AN END TO
THE PRECIP FROM NORTHWEST TO SOUTHEAST LATE THIS MORNING. CIGS
WILL BE SLOW TO IMPROVE...SO WILL HOLD ONTO THE LOW-END MVFR CIGS
THRU MID AFTN. AS SNOW DIMINISHES MIDDAY IT MAY BRIEFLY MIX WITH
DRIZZLE/FREEZING DRIZZLE.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH IN WINDS THROUGH PERIOD.
* HIGH FOR SNOW BY EARLY MORNING...MEDIUM FOR DETAILS OF CIG/VIS
AS WELL AS EXACT START/END TIMES.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...RAIN SHOWERS DEVELOPING BY EVENING. CHANCE OF
THUNDERSTORMS. MVFR/IFR POSSIBLE. BREEZY SOUTHEAST WINDS.
WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR EARLY. GUSTY WEST-
SOUTHWEST WINDS.
THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE.
FRIDAY...SLIGHT CHANCE OF SNOW SHOWERS AND MVFR EARLY.
SATURDAY...VFR.
RATZER
&&
.MARINE...
248 PM CDT
A HIGH PRESSURE RIDGE EXTENDS FROM NORTHERN
MANITOBA AND ONTARIO TO THE LOWER GREAT LAKES LATE THIS AFTERNOON.
NORTHEASTERLY WINDS WILL BE IN PLACE TONIGHT AND STEADILY TURN
EASTERLY MONDAY MORNING AS THE CENTER OF THE HIGH MOVES TO NORTHERN
LAKE HURON. THE HIGH WILL CONTINUE TO THE EAST ALLOWING WINDS TO
TURN SOUTHEASTERLY INTO MONDAY NIGHT. ATTENTION TURNS TO LOW
PRESSURE THAT WILL BE DEVELOPING IN THE LEE OF THE ROCKIES MONDAY
NIGHT THEN CONSOLIDATE AND STRENGTHEN ACROSS THE SOUTHERN PLAINS
TUESDAY EVENING. THE LOW WILL THEN LIFT NORTHEAST ACROSS EASTERN
IOWA AND THEN NORTHERN LAKE MICHIGAN INTO WEDNESDAY AFTERNOON WHILE
MAINTAINING STRENGTH. SOUTH TO SOUTHEAST WINDS WILL INCREASE TUESDAY
NIGHT...WITH A MORE DUE EAST DIRECTION ACROSS THE NORTH. WINDS WILL
FLIP SOUTHWEST SOUTH OF THE LOW TRACK AND REMAIN EAST TO NORTHEAST
TO THE NORTH ON WEDNESDAY. WARMER AIR WILL BE BUILDING IN SO A SHARP
STABLE LAYER WILL DEVELOP LIMITING WIND GUST POTENTIAL. STILL EXPECT
30 KT ON THE OPEN WATERS BUT WITH MIXING SPREADING OFFSHORE
NEARSHORE AREAS COULD EASILY SEE MID TO HIGH END GALES. THINGS
SETTLE DOWN WEDNESDAY NIGHT WHILE ANOTHER WEAKER LOW MOVES UP THE
OHIO VALLEY BUT STRONG HIGH PRESSURE WILL BUILD IN BEHIND IT. THIS
WILL BRING A SHIFT TO NORTH TO NORTHWEST WINDS ACROSS THE LAKE
THURSDAY WITH COLDER AIR ALLOWING MIXING TO DEEPEN AND BRINGING THE
POTENTIAL FOR A PERIOD OF LOWER END GALES. THE HIGH WILL MOVE
SOUTHWARD INTO THE PLAINS KEEPING WINDS NORTHERLY BUT ALLOWING
SPEEDS TO SLACKEN THROUGH THE END OF THE WEEK AND INTO THE WEEKEND.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008 UNTIL NOON MONDAY.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1143 PM CDT Sun Mar 22 2015
.UPDATE...
ISSUED AT 825 PM CDT SUN MAR 22 2015
Shortwave that will bring a wintry mix to parts of our area Monday
morning was pushing across central North Dakota with a lead wave
seen on the water vapor loop tracking into northwest Iowa. Narrow
band of frontogenetical forcing snows that occurred well to our
north late this afternoon into early this evening continuing to
to hold its position roughly from LaCrosse to Chicago. Latest
HRRR model suggests precip will start to push into our northern
areas between 07z-10z with RAP soundings indicating most of the
area to see surface temps above freezing, but barely, north of
I-74, when the precip starts to move in. However, there will be
enough evaporative cooling to see some sleet and possibly snow
to mix in at times initially, especially across our northern
counties where the low levels cool off significantly enough to
bring about the threat for more of a sleet-snow mixture. Further
south, the better lift doesn`t arrive until mid-morning and by
then surface temperatures should be warm enough to support some
light rain showers, which may mix with a little sleet at the
start. All in all, it looks as if areas along and north of the
I-74 corridor may see the mix move in just before the morning
rush so there may be some slick spots to deal with on the way
to work or school tomorrow morning.
Have made some minor adjustments to the forecast for the rest of
the evening hours, especially with the early evening temperatures
and precip timing for late tonight. Should have the updated zones
out by 900 pm.
&&
.SHORT TERM...(Tonight)
ISSUED AT 308 PM CDT SUN MAR 22 2015
Main forecast concern for this part of the forecast is with timing
of precipitation later tonight, and placement of any mixed precip.
Narrow band of light snow has been tracking from south central
Minnesota southeast into the Chicago area this afternoon. This has
been occurring along a baroclinic zone near a developing 850 mb warm
front. This thermal gradient will be slipping southward overnight,
as additional precipitation develops in response to a shortwave
currently pushing across South Dakota. Latest model trends have been
to slow the arrival of this precipitation in our area a bit,
reaching the Peoria area between 4 and 7 am. Forecast soundings
there showing a tongue of warm air around 800 mb reaching +2 to +3C
depending on the model, but quite a bit of dry air still present
below that, indicating potential for sleet. Any rain mixed in
initially will probably start to transition more toward snow as the
column aloft moistens and ice crystals are produced in the -10C to
-20C layer. Temperatures will be very close to freezing north of the
I-74 corridor, so will need to watch for any freezing rain potential
as well, but given the warmer ground temperatures as of late, the
icing threat would be more toward elevated surfaces. Additionally,
snow/sleet accumulation should be minimal as well. Arrival of the
precipitation further south along the I-72 corridor would likely not
be until after sunrise.
&&
.LONG TERM...(Monday through Sunday)
ISSUED AT 308 PM CDT SUN MAR 22 2015
Low pressure system moving into the upper Mississippi Valley area as
of Sunday afternoon, will track across northern IL and southern WI
Monday continuing to spread precipitation across central IL through
Monday afternoon. With lingering cold air near the surface and a
warm layer of southwesterly flow at 850 mb (~5000 ft), there will be
potential for a mix of winter precipitation. The warm layer aloft
looks sufficient to melt snow aloft to just north of the I-74
corridor, while surface/near surface temperatures below freezing
extend to just south of the I-74 corridor so this area will be
subject to mixed precipitation into early afternoon Monday.
Initially, sleet, snow and some potential for freezing drizzle early
in the morning, then mainly rain, and sleet into the early afternoon
as surface temperatures rise. Highs should eventually reach around
40 north of I-74 ranging up to the low 50s from Jacksonville to
Lawrenceville.
As the first clipper system exits central/SE IL late Monday evening,
another chance of rain showers arrive by overnight Monday night
ahead of a warm front associated with a low pressure system
approaching via the central Plains. Warm sector associated with this
low will bring modest values of CAPE and strong bulk shear late
Tuesday afternoon into Tuesday evening, although values still not
consistent model to model. Strongest convective potential appears to
be Tuesday afternoon over Missouri, but this activity could spread
into west central IL. SPC Day 3 severe weather outlook for Tue
afternoon/evening has a marginal risk for severe thunderstorms with
large hail/severe winds into our SW counties of Schuyler, Scott,
Morgan and Cass during Tue evening.
Forecast models continue to advertise diminishing chances for
precipitation Wed. as the system shifts E/NE of central IL. Breezy
WSW winds and partial clearing expected along with highs reaching
the upper 50s to mid 60s, which will be the warmest day of the week.
The 00Z extended forecast models continue to show strong upper level
trough digging southward into the Midwest Thursday and Friday
bringing mostly cloudy skies and a few light rain and snow showers
Thu night into Fri morning. This will bring much colder temperatures
with highs in upper 40s/lower 50s Thu and only in the upper
30s/lower 40s Friday. Temps slowly modify during the weekend with
highs in the 50s by Sunday. GFS and ECMWF models show an upper level
closed low moving into the western great lakes Sunday and returning
chance of rain, or possibly snow showers to central IL.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1125 PM CDT SUN MAR 22 2015
VFR conditions are expected thru the 09z-11z time frame before some
light precip develops from northwest to southeast helping to bring
MVFR cigs to PIA and BMI initially, and then over the remainder of
the sites by 15-16z as the area of precip shifts southeast. Precip
type still an issue as it depends on what forecast sounding you
look at with the overall consensus trending towards a mix of
rain/sleet and snow and even the slight chance for a brief period
of light freezing rain across our northern TAF sites. At this time,
will opt to make it a rain/sleet/snow mix across the north with some
rain and sleet by the time the precip reaches CMI by mid morning.
However, surface temperatures will be very close to the freezing
mark thru about 15z so some patchy slippery spots will be possible,
however, with the recent warm weather we have had, not thinking we
are going to see a widespread or prolonged period of icing at this
point over PIA and BMI.
Some of the high resolution radar simulations hint at the possibility
for some convective elements embedded in the band of precip which
would enhance the precip rates and may briefly change over to a period
of light to moderate snow and sleet in the 10z-14z time frame, again
mainly affecting the I-74 corridor (PIA, BMI). Most of the precip should
push east of the area by 20z as the shortwave moves away from central
IL. Surface winds will continue from an easterly direction at 10 to
15 kts tonight and continue that way on Monday, with a few gusts to
20 kts possible at times.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1150 PM CDT Sun Mar 22 2015
...AVIATION UPDATE...
.UPDATE...
Issued at 1005 PM CDT SUN MAR 22 2015
The latest NAM and RAP forecast soundings are less bullish with
the mid level moisture than earlier progs, and this may be the
reason why elevated storms have failed to form along the boundary.
The 00Z RAOB from TOP and OAX show there is still quite a bit of
moistening to take place and there is an AC deck behind the front.
However there has not been much development in these clouds and
with no real large scale forcing to lift parcels, think
convergence along the boundary from the low level jet is the only
mechanism to get storms to go. This convergence has not been
strong enough to this point for storms that developed earlier to
maintain an updraft. With model progs veering the low level jet to
the southwest and west, this convergence should weaken. With all
of this in mind, have paired back the slight chance pops to the
northeast corner of the forecast area. Any storm is likely to be
high based and may not even produce measurable precip with the
MUCAPE being very limited if there is any at all.
&&
.SHORT TERM...(This Evening through Monday)
Issued at 232 PM CDT SUN MAR 22 2015
A weak shortwave in the northwest flow aloft will track over the
upper Midwest this evening and overnight. This will drag a cold
front through the area, which is currently located in NW KS and
central NE. Ahead of the front low level moisture advection has
worked into central KS this morning as evident by the cumulus field
that has developed. This will inhibit how low the dew points mix out
in that region, while further east the dew points mix out much lower
into the 30s. There is decent agreement on the timing of the front,
which should enter north central KS around sunset. As the front
moves southeastward into the slightly better moisture an isolated
shower may develop along the front. There will be a decent amount of
dry air closer to the surface which may make it difficult for
precipitation to accumulate much over a few hundredths. With this
increased moisture the elevated cape overnight should range from
300-500 j/kg, therefore can not rule out the possibility of some
thunder. If the showers can develop it will be brief as the front
continues to progress eastward, and dry air moves behind the front
in the 900-850 MB layer. The highest chance are across far northeast
and east central KS.
This front is forecast to stall out in far southern KS tomorrow
morning. Overnight low temperatures will range from the upper 40s in
southeast KS to the upper 30s in north central KS. Cooler air moving
in behind the front places highs tomorrow in the 60s. During the day
tomorrow a shortwave will track over the central Rockies and
eventually the central plains overnight. Increased southerly flow
ahead of the wave lifts the front back to the north. Also, an
increasing low level jet advects higher moisture from the south into
southern KS. This higher moisture should help to erode the cap along
and north of the warm front. Showers and thunderstorms will increase
in coverage in the late afternoon and early evening.
.LONG TERM...(Monday Night through Sunday)
Issued at 232 PM CDT SUN MAR 22 2015
Monday Night - Thunderstorm coverage will increase through the
evening and overspread the area through the night. This will be in
response to a strong low level jet bringing quick moisture
advection, warm air advection, and enhanced isentropic ascent
underneath a plume of fairly steep mid level lapse rates. A broad
area of mid/upper level forcing will also overspread the area
during the evening and overnight hours. The moisture influx into
the region will be nearly continuous, as will storm development,
but the focus area for development will gradually shift to the
north and east and should exit the forecast area near or shortly
after sunrise on Tuesday. MUCAPE is likely to exceed 1000 J/kg at
times with strong mid/upper flow supportive of some elevated
supercell structures and large hail associated with a few of these
storms. Pockets of heavy rainfall will also be possible with the
continued storm development through the night.
Tuesday - The weather scenario on Tuesday remains complex but at
least most model guidance is beginning to resolve low level
features that fit the conceptual model of this type of strong
negatively tilted short wave trough. The upper short wave is still
forecast to deepen sharply during the day on Tuesday as the heart
of the trough tracks from SW Colorado into far southeast NE. A
strong mid level jet max will track along the southern periphery
of the trough, and expect surface low pressure to translate from
SW Kansas into NW Missouri. The NAM is a notable outlier in the
track of the surface low and tracks it south of the forecast area
(although still pulling south winds and higher dewpoints well
north into the forecast area with another weak sfc low a bit
farther northwest. Moisture return will be efficient on Monday
night into Tuesday ahead of this system, but the moisture source
will be modified continental air so looking at max dewpoints only
in the mid to perhaps upper 50s in the warm sector. Expect to see
at least some partial clearing and warming in the warm sector in
SBCAPE may exceed 1000 J/kg. Deep layer wind shear will be very
strong, and if storms develop they should quickly obtain supercell
structure as they move quickly to the east. Given the strong
dynamics with this storm system, it would now make sense for
storms to develop a bit earlier in the afternoon along the dry
line and under the rapid mid level cooling associated with the
upper trough. Feel that the ECMWF (which is quite similar to the
GFS and GEM) rendition of thunderstorm initiation occurring in the
local forecast area with some strengthening and organization
possible as they cross eastern KS near/south of the surface low
track. So, will re-introduce the potential for some strong to
severe thunderstorms for a few hours during the early/mid
afternoon on Tuesday with hail and damaging winds the main
hazards in the local forecast area. Aside from the warm sector,
elevated instability remains in place north of the surface low
track as well, and will likely support scattered showers and a few
thunderstorms as the system moves through. With the very strong
trough aloft, there may be some chance for a bit of hail even
north of the low. It now appears that the driest air behind the
system may remain just south and west of the area, so while it
will be windy late Tuesday the RH may remain above critical levels
locally and likely rainfall on Monday night could limit the fire
danger.
Tuesday night - Saturday - This system moves quickly northeast and
out of the area and expect dry conditions after sunset on Tuesday.
Wednesday will still be fairly warm but another strong upper
trough will dive across the Plains from the northwest with a much
cooler airmass moving in with it. Depending on airmass moisture in
place in advance of this system, there could be scattered showers
with the front passage late Wednesday. Temperatures then become
much cooler and there appears to be some strong potential for a
freeze...and perhaps a hard freeze...Friday morning and Saturday
morning. Currently have lows in the upper 20s but if skies are
clear on Saturday morning and the surface high is perfectly timed,
could end up in the low to middle 20s. The recent warm
temperatures may increase the impacts of a hard freeze but will
have to look deeper into this and how far along the growing season
is at this time. Warmer temperatures are then in store again for
next weekend.
&&
.AVIATION...(For the 06Z TAFs through 06Z Monday Night)
Issued at 1150 PM CDT SUN MAR 22 2015
VFR conditions should prevail through the day Monday. Convection
along the boundary continues to look unlikely as the low level jet
veers to the southwest. Otherwise, return flow and overrunning of
the boundary Monday evening should lead to widespread showers with
some thunderstorms. Have initially included some CIGS between 2
and 3 KFT, but they may eventually end up lower as the MOS data is
suggesting some 1 to 2 KFT CIGS by 06Z Tues.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...Wolters
SHORT TERM...Sanders
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS JACKSON KY
112 AM EDT MON MAR 23 2015
.UPDATE...
ISSUED AT 942 PM EDT SUN MAR 22 2015
DID A MINOR UPDATE TO TWEAK THE HOURLY T AND TD GRIDS PER THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
UPDATE ISSUED AT 645 PM EDT SUN MAR 22 2015
BUMPED UP SKY COVER TO BETTER REFLECT CURRENT CONDITIONS...AND
ALIGNED TEMPS/DEW POINTS WITH MOST RECENT OBS. KEEPING ON EYE ON
SOME LIGHT RADAR RETURNS...BUT CURRENT THINKING IS THAT ANY
MEASURABLE PRECIP WILL STAY SOUTH OF THE AREA TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 400 PM EDT SUN MAR 22 2015
19Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING IN FROM THE NORTH
WITH LOW PRESSURE SKIRTING THE BOUNDARY JUST TO OUR SOUTH. ON
RADAR...LIGHT RETURNS KEEP TRYING TO SNEAK ACROSS OUR BORDER WITH
TENNESSEE...BUT SO FAR THERE HAVE NOT BEEN ANY OBS OR REPORTS OF
ANYTHING REACHING THE GROUND IN KENTUCKY. THICKENING HIGH CLOUDS
ARE SEEPING NORTH ASSOCIATED WITH THE SOUTHERN SYSTEMS...BUT ONLY
RECENTLY HAVE THE CLOUDS GOTTEN OPAQUE ENOUGH TO BLOCK THE SUN.
WITH THE FILTERED SUNSHINE...TEMPERATURES WERE ABLE TO CLIMB INTO
THE LOW 60S ACROSS THE SOUTH AND THE MID 50S TO THE NORTH.
DEWPOINTS BASICALLY HELD STEADY THROUGH THE DAY SO THAT THEY STILL
VARY FROM THE UPPER 20S IN THE NORTH TO LOW 40S IN THE SOUTH.
MEANWHILE...WINDS REMAIN MAINLY FROM THE NORTHEAST AT 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK SOUTHERN STREAM TROUGH PASSING THROUGH THE
DEEP SOUTH WHILE SOME ENERGY SLIPS INTO THE OHIO VALLEY LATE
MONDAY IN THE NORTHERN STREAM. HEIGHTS WILL GRADUALLY RISE THROUGH
TUESDAY MORNING AS THE SOUTHERN TROUGH DEPARTS...EVEN WITH THE
NORTHERN ENERGY SCRAPING BY MONDAY NIGHT. GIVEN THE GENERAL MODEL
AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX
DETAILS THROUGH THE SHORT TERM.
SENSIBLE WEATHER WILL FEATURE THE SMALL POTENTIAL FOR SPRINKLES OR
LIGHT RAIN IN FAR SOUTHERN PARTS OF THE CWA TONIGHT. OTHERWISE
PARTLY TO MOSTLY CLOUDY SKIES WILL DOMINATE HELPING TO KEEP THE
LID ON THE WORST OF THE COOLING OVERNIGHT. FOR MONDAY...HIGH
CLOUDS WILL CONTINUE TO PLAGUE THE AREA AS WE WILL BE BETWEEN THE
SYSTEMS ON OUR FRINGES. LATER THAT NIGHT THERE WILL BE A SMALL
CHANCE FOR RAIN IN THE NORTHERNMOST PARTS OF EASTERN KENTUCKY AS
A DEVELOPING...BUT MOSTLY DRY...WARM FRONT LIFTS THROUGH THE
AREA.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS
INTO MONDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD.
AS FOR POPS...ENDED UP IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 335 PM EDT SUN MAR 22 2015
AN UPPER LEVEL TROUGH DIGGING INTO THE NORTHERN PLAINS WILL DRIVE A
WARM FRONT NORTHWARD ACROSS OUR AREA ON TUESDAY. WHILE MOISTURE IS
MEAGER WITH THIS FRONT...MODELS CONTINUE TO INDICATE THE POTENTIAL
FOR A FEW SHOWERS. THIS WARM FRONT WILL SHIFT NORTH OF OUR AREA
TUESDAY NIGHT. A WEAKENING SFC COLD FRONT ASSOCIATED WITH LOW
PRESSURE OVER THE GREAT LAKES WILL DROP DOWN ACROSS THE AREA ON
WEDNESDAY WHILE THE SUPPORTING UPPER LEVEL TROUGH EVENTUALLY OUT
RUNS ALL OF ITS SFC FEATURES. WHILE MOISTURE REMAINS MEAGER WITH
THIS SYSTEM...ISOLATED TO SCATTERED SHOWERS AND PERHAPS A STRAY
THUNDERSTORM CAN NOT BE RULED OUT DURING THE DAY WEDNESDAY.
ANOTHER MORE SUBSTANTIAL...DEEPER TROUGH WILL REENERGIZE THE
BOUNDARY LEFT IN PLACE ACROSS THE REGION WEDNESDAY NIGHT INTO
THURSDAY. THERE WILL BE ENOUGH ENERGY WITH THIS SECOND UPPER TROUGH
THAT WE CAN EXPECT NUMEROUS SHOWERS TO DEVELOP ACROSS OUR AREA AS
ITS INDUCED SFC LOW DEVELOPS AND PUSHES UP THE MID MISSISSIPPI...
LOWER OHIO VALLEY. THIS WILL ALLOW THE SFC FRONT TO REORGANIZE AND
BEGIN ITS PUSH EASTWARD AGAIN. SFC BASED INSTABILITY DOES NOT LOOK
AS IMPRESSIVE BUT SHOULD BE ENOUGH TO KEEP MENTION OF A FEW
THUNDERSTORMS IN THE FORECAST. WHILE THE ENDS GENERALLY REMAIN THE
SAME WITH RESPECT TO SENSIBLE WEATHER...BOTH THE GFS AND ECMWF ARE
IN DECENT AGREEMENT WITH THIS SCENARIO...THE GFS DOES APPEAR MORE
AGGRESSIVE AND WELL DEFINED WITH ALL THE SFC FEATURES THAN THE
ECMWF. IN ADDITION...MODELS SEEM TO BE TRENDING A BIT SLOWER
OVERALL WITH THE EVOLUTION OF THIS PHASE OF THE EXTENDED.
IN ADDITION...OUR PATTERN TURNS MUCH COLDER FROM THURSDAY NIGHT INTO
THE WEEKEND AS A LARGE CANADIAN SFC HIGH PRESSURE SYSTEM SETTLES
OVER THE REGION. UPPER LEVEL ENERGY CONTINUES TO DIG IN FROM THE
NORTHWEST...DEEPENING THE TROUGH OVER THE OHIO AND TENNESSEE
VALLEYS. DEEPER MOISTURE WILL EXIT WITH THE FRONT BY THURSDAY
NIGHT...BUT AN UNSTABLE BOUNDARY LAYER WILL REMAIN IN PLACE AS THE
CORE OF THE TROUGH SWINGS THROUGH ON FRIDAY. WITH STEEP LAPSE
RATES...A FEW RAIN SHOWERS CAN NOT BE RULED OUT. IF FREEZING LEVELS
DROP LOW ENOUGH WE COULD EVEN SEE SOME WET SNOW MIX IN OVER THE
HIGHER TERRAIN. STILL SOME UNCERTAINTY IN THE MODELS WITH THE AMOUNT
OF MOISTURE AND COLD AIR COMING IN...BUT THERE SEEMS TO BE A GENERAL
CONSENSUS OF H850 TEMPS DROPPING TO AROUND -10C OVERHEAD BY SATURDAY
MORNING. THIS COULD RESULT IN A WIDESPREAD FREEZE SATURDAY MORNING
IF SFC HIGH PRESSURE BECOMES MORE CENTERED OVER EASTERN KENTUCKY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 112 AM EDT MON MAR 23 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. A SURFACE HIGH
PUSHES SOUTH TONIGHT AND INTO MONDAY AS LOW PRESSURE SCOOTS PAST
TO THE SOUTH. HIGH CLOUDS OF VARYING OPACITY FROM THE SOUTHERN LOW
WILL COVER THE REGION THROUGH THE NIGHT BUT THESE WILL EXIT TO THE
EAST ON MONDAY AS THE LOW PULLS AWAY. WINDS THROUGH MUCH OF THE
TAF PERIOD WILL REMAIN GENERALLY LIGHT FROM THE NORTH TO
NORTHEAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...GREIF
LONG TERM...ABE/RAY
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
510 AM EDT MON MAR 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 510 AM EDT MON MAR 23 2015
QUIET WEATHER WILL CONTINUE THRU THE SHORT TERM. WATER VAPOR IMAGERY
AND RAP ANALYSIS SHOW A COUPLE OF SHORTWAVES MOVING THRU THE NW FLOW
OVER THE NRN PLAINS. ONE WAVE IS MOVING ACROSS IA/SRN MN WITH A
SECOND MORE WELL-DEFINED WAVE TO THE NW IN SRN MANITOBA. ALTHOUGH
THE NRN WAVE IS MORE DEFINED...THE SRN WAVE IS PRODUCING MORE
SIGNIFICANT PCPN DUE TO THE COMBINATION OF BETTER MOISTURE AND MUCH
STRONGER FGEN. NOTHING MORE THAN SOME HIGH CLOUDS HAVE SPREAD INTO
UPPER MI OVERNIGHT ON THE NRN EDGE OF THE SRN WAVE. WITH HIGH PRES
CENTERED JUST NE OF LAKE SUPERIOR DOMINATING THE UPPER LAKES...WINDS
HAVE BEEN LIGHT/CALM ACROSS THE FCST AREA DURING THE NIGHT. THIS HAS
ALLOWED TEMPS IN TRADITIONAL COLD SPOTS TO DROP OFF INTO THE SINGLE
DIGITS ABOVE ZERO OVER THE E WHERE CLOUDS HAVE BEEN THINNEST.
ALTHOUGH UPSTREAM SHORTWAVE IN SRN MANITOBA IS WELL-DEFINED NOW AND
HAS AN ASSOCIATED AREA OF SNOW...MODELS ARE IN EXCELLENT AGREEMENT
SHOWING THIS WAVE WEAKENING AND SHEARING SE IN THE CONFLUENT FLOW
BTWN DEPARTING TROF IN SE CANADA/NE CONUS AND BUILDING RIDGE MOVING
OUT OVER THE NRN PLAINS IN ADVANCE OF COMPLEX OF SHORTWAVE ENERGY
MOVING ACROSS THE PACIFIC NW/NRN ROCKIES. SO...WHILE CURRENT LOOK OF
THE WAVE BRINGS SOME CONCERN THAT -SN/FLURRIES COULD STILL REACH THE
FAR WRN FCST AREA THIS EVENING...WILL MAINTAIN A DRY FCST SINCE
MODELS ARE IN SUCH GOOD AGREEMENT ON THE PCPN DISSIPATING. THE DRY
FCST IS STRONGLY SUPPORTED BY THE VERY DRY ANTECEDANT AIR MASS OVER
THE AREA PER OBSERVED 00Z SOUNDINGS AT KINL/KGRB. THIS DRY AIR MASS
WILL BE EVEN MORE DIFFICULT TO OVERCOME SINCE THE WAVE WILL BE
WEAKENING.
MAINLY HIGH CLOUDS AFFECTING THE AREA TODAY WILL CLEAR OUT TONIGHT
AS FCST SOUNDINGS SHOW NOTABLE DRYING IN THE UPPER LEVELS AS
MID/UPPER LEVEL RIDGE APPROACHES. WITH HIGH PRES JUST E OF THE AREA
TODAY...LIGHT EASTERLY WINDS WILL TAKE ON A LAKE BREEZE COMPONENT TO
KEEP AREAS NEAR THE GREAT LAKES COOLER...THOUGH THIS COOLING WILL BE
MORE LIMITED NEAR THE WRN SHORE OF UPPER MI. EXPECT HIGH TEMPS TODAY
TO RANGE FROM THE UPPER 20S/AROUND 30F TO AROUND 40F. IT WILL BE
COOLEST OVER THE E...NEAR LAKE SUPERIOR FROM THE KEWEENAW EASTWARD
AND NEAR LAKE MICHIGAN...AND IT WILL BE WARMEST OVER THE FAR W WHERE
DOWNSLOPING WILL AID WARMING. LEANED TOWARD THE LOWER SIDE OF
GUIDANCE TONIGHT GIVEN EXPECTED CLEARING SKIES AND CONTINUED LIGHT
WINDS. THE COLDEST BIAS CORRECTED GUIDANCE HAS MINS BLO ZERO TONIGHT
AT SOME OF THE USUAL COLD SPOTS. THAT SEEMS TOO LOW GIVEN LIGHT
SOUTHERLY FLOW AND CONTINUED MODERATION OF AIR MASS. IF ANY
LOCATIONS DO FALL SUBZERO...IT WOULD OCCUR OVER THE FAR ERN FCST
AREA CLOSER TO DEPARTING HIGH PRES. IN GENERAL...EXPECT SOME SINGLE
DIGITS ABOVE ZERO IN THE INTERIOR CNTRL AND E. OTHERWISE...MINS WILL
BE IN THE TEENS WITH SOME LOWER 20S W.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 228 AM EDT MON MAR 23 2015
AFTERNOON HIGHS TUESDAY WILL BE ON AVERAGE 10F WARMER THAN TODAY.
THIS WILL BE THANKS TO THE WAA S WINDS AND 850MB TEMPS RISING TO 0
TO -3C BY LATE AFTERNOON AS THE SFC HIGH OVER FAR SE ONTARIO
CONTINUES TO EXIT THE PICTURE. THE TRADITIONAL DOWNSLOPE LOCATIONS
OVER THE W HALF NEAR LAKE SUPERIOR SHOULD BE ABLE TO CLIMB INTO THE
MID TO UPPER 40S. A FEW 50F READINGS WILL NOT BE OUT OF THE
QUESTION.
OUR EYES WILL BE ON THE SFC LOW OVER THE DAKOTAS TUESDAY...AND THE S
LOW SHIFTING FROM CENTRAL KS TO W IA/MO BY THE END OF THE DAY.
TAKING A LOOK AT 500MB THE S SHORTWAVE OVER THE CENTRAL PLAINS
TUESDAY MORNING WILL CONTINUE TO STRENGTHEN. UNLIKE WHAT WE HAVE
SEEN FROM SYSTEMS RECENTLY...THIS ONE HAS SOME GOOD MOISTURE TO WORK
WITH...STREAMING N FROM THE W GULF OF MEXICO. THE NEARLY STACKED
SYSTEM WILL SWING ACROSS WI/W LOWER MI BY DAYBREAK
WEDNESDAY...PUSHING MIXED PRECIP ALONG THE WI BORDER BY 06Z
WEDNESDAY. DRY SOUNDINGS BELOW 800MB INDICATE THAT IT MAY TAKE A BIT
FOR THE NEAR-SFC LAYER TO MOISTEN ENOUGH FOR PRECIP TO FALL. EXPECT
MAINLY SNOW IF THE GFS IS CORRECT. THE 18Z AND 00Z GFS RUNS...WITH
THE MOST E TRACK OF THE SFC LOW...KEEPS ENOUGH COLD ENOUGH AIR
OVERHEAD TO KEEP MOST OF THE PRECIP STAYING AS SNOW EVEN ALONG THE
WI BORDER AND OUT E /ONLY A BIT OF FZRN AROUND MNM WEDNESDAY
MORNING/. THE QPF IS ON THE ORDER OF 0.1-0.2 IN LESS ON THE LATEST
RUN. THE NAM CONTINUES TO GO HIGH ON THE FZRN POTENTIAL. WHILE THE
18Z RUN OF THE NAM WAS A BIT COLDER/THE 00Z RUN HAS THE SFC LOW JUST
SLIGHTLY DEEPER AND TO THE W. HOWEVER...THE QPF HAS BEEN VERY
JUMPY...WITH RUN TO RUN CONSISTENCY ISSUES. WILL NOT GO COMPLETELY
WITH THE NAM OR GFS SOLUTIONS. THE SOLUTIONS DIVERGE AS EARLY AS
TUESDAY AFTERNOON OVER E KS/W MO...WITH THE NAM/ECMWF ON THE SLOW
SIDE COMPARED TO THE GFS. IT WILL BE INTERESTING TO SEE HOW THE
SOLUTIONS PAN OUT OVER THE NEXT DAY OR SO. WILL KEEP THE MENTION OF
SNOW AND MIXED PRECIP IN THE HWO...WITH SOME SLIGHT ADJUSTMENT. WILL
CONTINUE WITH MODERATE TO LOWER CONFIDENCE WITH THIS PERIOD.
WHILE THE S SFC LOW SHIFTS ACROSS E UPPER MI/N LOWER MI WEDNESDAY
AFTERNOON THE LOW THAT WAS IN THE DAKOTAS WILL SLIDE ACROSS N MN. SO
EVEN THOUGH THE INITIAL LOW SHIFTS ACROSS E ONTARIO AND INTO S
QUEBEC THURSDAY EVENING..LOW PRESSURE WILL LINGER ACROSS UPPER MI
THROUGH THE NIGHT AS THE SECONDARY LOW SHIFTS IN.
THE DGZ FINALLY FALLS WELL INTO THE MOISTURE LAYER OVERNIGHT
WEDNESDAY NIGHT THROUGH EARLY FRIDAY MORNING AS THIS SECONDARY LOW
SINKS ACROSS N LOWER MI THURSDAY MORNING. ALTHOUGH 850MB TEMPS FROM
THURSDAY AFTERNOON ON WILL BE -16C OR COLDER OVER THE W HALF...WINDS
LOOK TO BE SHIFTING QUITE A BIT...ANYWHERE OUT OF THE NW TO N TO NE.
THIS WILL LIMIT THE DEVELOPMENT OF STRONG LES BANDS. STILL...LES
WILL BE POSSIBLE. AN ADDITIONAL 2-5IN OF NEW SNOW WILL BE POSSIBLE
OVER THE LONGER PERIOD OF WEDNESDAY NIGHT THROUGH EARLY
FRIDAY...WITH THE HIGHEST AMOUNTS OVER THE FAVORABLE N WIND
SNOWBELTS.
LOOK FOR DRY WEATHER TO TAKE HOLD AGAIN FRIDAY AFTERNOON...WHEN THE
LARGE SFC HIGH SET UP FROM CENTRAL CANADA THROUGH MUCH OF THE
CENTRAL PLAINS EDGES INTO THE UPPER GREAT LAKES. THIS RIDGE OF HIGH
PRESSURE WILL REMAIN ACROSS UPPER MI INTO EARLY SATURDAY...BEFORE
EXITING TO THE SSE. GIVEN A MOSTLY CLEAR SKY AND ASSUMING NO
LINGERING LES...SATURDAY MORNING COULD BE PRETTY CHILLY IN THE
TRADITIONAL COLD SPOTS OF INTERIOR UPPER MI. DID ADJUST VALUES DOWN
SLIGHTLY FROM THE OVERALL MODEL BLEND.
LOW PRESSURE OVER MUCH OF CENTRAL CANADA ON SATURDAY WILL SWING A
TROUGH ACROSS ONTARIO SATURDAY NIGHT THROUGH SUNDAY. WHILE THE GFS
IS MORE PROGRESSIVE WITH THIS SYSTEM...THE ECMWF DEEPENS AN OFFSHOOT
OF THE MAIN LOW OVER ONTARIO AVERAGING 985MB. AT THIS POINT BOTH THE
ECMWF AND GFS PIN POINT THE E HALF OF UPPER MI TO GET 0.25IN OR MORE
OF LIQUID LATE SATURDAY NIGHT/EARLY SUNDAY MORNING. WITH 850MB TEMPS
OF -3 TO -5C A HEAVY WET SNOW IS MOST LIKELY. WILL HOLD OFF ON ANY
MENTION IN THE HWO QUITE YET...AS SEVERAL CHANGES WILL BE POSSIBLE
BETWEEN NOW AND THEN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 143 AM EDT MON MAR 23 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THROUGH THE TAF PERIOD
AS A HIGH PRESSURE RIDGE REMAINS OVER THE AREA. A DISTURBANCE MOVING
THROUGH SOUTHERN MINNESOTA/WISCONSIN WILL STREAM HIGH CLOUDS ACROSS
UPPER MICHIGAN OVERNIGHT THROUGH TODAY. THE CLOUDS ARE EXPECTED TO
BE THE THICKEST OVER THE SOUTHWEST HALF OF UPPER MICHIGAN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 510 AM EDT MON MAR 23 2015
HIGH PRES JUST NE OF LAKE SUPERIOR WILL DRIFT SOUTHEAST...REACHING
SOUTHERN ONTARIO BY TUE MORNING AND THE MID ATLANTIC STATES TUE
AFTN. WITH PRES GRADIENT REMAINING WEAK...WINDS WILL BE BLO 20KT
ACROSS LAKE SUPERIOR. A LOW PRESSURE SYSTEM OVER THE CENTRAL PLAINS
TUE WILL TRACK NE...CROSSING FAR NRN LWR MI WED AFTN. WINDS SHOULD
NOT STRENGTHEN MUCH AHEAD OF THIS FEATURE AS PRES GRADIENT DOES NOT
TIGHTEN SIGNIFICANTLY. STRONGEST WINDS WILL OCCUR THU AS HIGH PRES
BUILDS S TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO
THE UPPER LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...
AND IT`S NOT OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR
FOR A TIME. WINDS WILL THEN DIMINISH FRI AS A HIGH PRESSURE RIDGE
MOVES OVER THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS BILLINGS MT
347 AM MDT MON MAR 23 2015
.SHORT TERM...VALID FOR TDY AND TUE...
A RELATIVELY ACTIVE PERIOD WITH SHOWER CHANCES IS IN STORE DURING
THE NEXT TWO DAYS...WITH THE GREATEST CHANCE OF MOISTURE FOR MOST
AREAS COMING LATE THIS AFTERNOON THROUGH TONIGHT. AREA MOUNTAINS
WILL GET SEVERAL INCHES OF SNOW IN THIS PATTERN AS WELL.
FIRST OF ALL...WE HAVE PATCHY FOG IN THE FORECAST THROUGH THE MID
MORNING IN THE EKALAKA AND BAKER AREAS...WHERE VISIBILITY IS DOWN
TO 1/4SM AS OF 09 UTC. HRRR SIMULATIONS SUGGEST THE FOG SHOULD BE
DISSIPATING BY AROUND 15 UTC.
TODAY...A MILD DAY IS IN STORE WITH HIGHS MAINLY IN THE 60S F OUT
AHEAD OF THE APPROACHING 500-MB TROUGH. THE SPEED AT WHICH CLOUDS
THICKEN COULD PRODUCE SOME ERROR IN FORECAST HIGHS THOUGH. SHOWERS
WILL LIKELY BEGIN TO DEVELOP AND/OR MOVE INTO WESTERN PORTIONS OF
SOUTH CENTRAL MT THIS AFTERNOON AS HEIGHT FALLS COMMENCE AND LEAD
TO INCREASING QG-FORCING ALOFT. WE RELIED ON THE 00 UTC MODELS AND
MORE CONTEMPORARY HIGH-RESOLUTION AND CONVECTION-ALLOWING GUIDANCE
LIKE THE RAP AND HRRR TO HOLD OFF THE CHANCE OF SHOWERS WITHIN THE
FORECAST FOR BILLINGS EASTWARD ACROSS SOUTHEASTERN MT UNTIL 21 UTC
/3 PM MDT/. SPEAKING OF SOUTHEASTERN MT...POPS THIS AFTERNOON OVER
THAT PART OF THE STATE ARE CONDITIONAL ON WEAK INSTABILITY FORMING
AND CONTRIBUTING TO CONVECTIVE ELEMENTS DEEPENING ENOUGH TO YIELD
PRECIPITATION. THAT/S FAR FROM CLEAR...THOUGH THE FAVORED NON-NAM
SET OF 00 UTC GUIDANCE LIKE THE GFS DOES SUPPORT SOME 100-200 J/KG
OF MUCAPE THERE /AND BACK FURTHER WEST AROUND LIVINGSTON/ DUE TO A
PLUME OF STEEP MID-LEVEL LAPSE RATES EXCEEDING 8 C/KM...SO WE DID
LEAVE A SLIGHT CHANCE OF THUNDERSTORMS IN WITH THE SHOWERS IN BOTH
OF THOSE AREAS THIS AFTERNOON. WE LEFT THEM IN SOUTHEASTERN MT FOR
THE EARLY EVENING FOR SIMILAR REASONS.
TONIGHT...A RATHER STRONG...BUT QUICK-MOVING BATCH OF FORCING WILL
CROSS THE AREA AND LIKELY YIELD AN EASTWARD-MOVING ROUND OF SHOWER
ACTIVITY. WE HAVE THE HIGHEST /LIKELY-RANGE/ POPS IN PLACE ACROSS
SOUTHEASTERN MT WHERE THAT FORCING WITH THE 500-MB TROUGH LOOKS TO
INTERCEPT A NARROW RIBBON OF HIGHER MOISTURE THAT THE 00 UTC MODEL
GUIDANCE FORECASTS TO MOVE NORTHWARD ALONG THE HIGH PLAINS WITH AN
AXIS OF PRECIPITABLE WATER VALUES OF 0.50 INCHES MOVING OUT OF THE
SOUTHERN PLAINS AND INTO EASTERN MT OVERNIGHT. THE DODGE CITY...KS
OBSERVED SOUNDING FROM 00 UTC MARCH 23RD DID SAMPLE A PRECIPITABLE
WATER VALUE OF 0.42 INCHES...WHICH SUGGESTS THE GUIDANCE DOES HAVE
A HANDLE ON THIS SCENARIO. MOISTURE TOTALS WITH THE HIGHEST CHANCE
OF SOME QUARTER INCH RAIN TOTALS WILL THUS ALSO BE IN SOUTHEASTERN
MT. MEANWHILE...TIME-LAGGED AND ONE-RUN ENSEMBLE GUIDANCE BACK TO
THE WEST IN BILLINGS CONTINUES TO SUGGEST THE CITY WILL LIKELY GET
0.05 INCHES OR LESS OF MOISTURE OUT OF THIS SYSTEM.
TUESDAY INTO TUESDAY NIGHT...COOLER AND UNSETTLED WEATHER WILL BE
THE THEME BEHIND TONIGHT/S WAVE PASSAGE. NOTE THAT THE 00 UTC GEM
AND ECMWF ACTUALLY SUGGEST MORE BONAFIDE WRAP-AROUND MOISTURE AND
POSSIBLY EVEN SNOW IN BAKER EARLY TUESDAY MORNING AS THEY PLACE A
GREATER EMPHASIS ON THE NORTHERN PIECE OF THE TROUGH ALOFT. WE DO
NEED TO KEEP AN EYE ON THAT...BUT CONFIDENCE IN HOW THAT WILL END
UP PLAYING OUT IS LOW. OTHERWISE...THERE IS GREATER CONFIDENCE IN
ANOTHER WEAKER SHORTWAVE TROUGH DROPPING ACROSS SOUTH CENTRAL MT
TUESDAY AFTERNOON AND EVENING WITH CONVECTIVELY-AIDED SHOWERS OF
RAIN AND EVENTUALLY SNOW SHOWERS BY TUESDAY NIGHT. THIS SITUATION
IS ONE THAT CAN YIELD ACCUMULATING SNOW IN THE FOOTHILLS LIKE AT
RED LODGE...AND IF GUIDANCE REMAINS CONSISTENT IN ITS SIMULATION
OF THIS SCENARIO THEN WE MAY NEED TO INCREASE SNOW AMOUNTS WITH A
LATER FORECAST RELEASE IN THE FOOTHILLS. SCHULTZ
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
COOLER AND UNSETTLED NORTHERLY FLOW WILL REMAIN OVER THE REGION
THROUGH THURSDAY. LAPSE RATES WILL BE STEEPEST ON WEDNESDAY WITH
SOME DIURNAL RAIN/SNOW SHOWERS ANTICIPATED...ESPECIALLY IN NW FLOW
FAVORED AREAS...BUT W/OUT MUCH SYNOPTIC FORCING. A SURGE OF
MOISTURE SPILLING OVER THE WESTERN CONUS RIDGE WILL KEEP THE
POTENTIAL FOR SHOWER ACTIVITY GOING WEDNESDAY NIGHT AND THURSDAY.
LATEST MODEL TRENDS SUGGEST BACKDOORING COOLING WHICH WILL
INCREASE THE LOW LEVEL BAROCLINICITY IN OUR CWA...THOUGH MODELS
ARE DIFFERENT IN WHERE THEY PAINT HIGHEST QPF. IF SFC TEMPS REMAIN
COOL ENOUGH WE COULD SEE SOME WET SNOWFALL IN A COMBINATION OF OUR
N-NW FLOW UPSLOPE AREAS AND ALONG SFC BOUNDARY. HAVE RAISED POPS
IN OUR SOUTH CENTRAL PARTS THURSDAY INTO THURSDAY NIGHT...AND HAVE
LOWERED TEMPS A BIT IN OUR CENTRAL AND EAST. OF COURSE THE NW FLOW
ALOFT WILL FAVOR THE BIGHORN MTNS FOR SNOWFALL THRU THE PERIOD.
STRONG RIDGE ALONG THE PAC COAST WILL BEGIN TO SHIFT EAST ON
FRIDAY BRINGING US RAPID DOWNSLOPE WARMING AS HEIGHTS SURGE INTO
THE 570S ACROSS WESTERN AND CENTRAL MT. SHOULD SEE HIGH TEMPS BACK
NEAR 70F IN OUR WEST BUT PROXIMITY TO SLOWER DEPARTING SFC HIGH IN
THE PLAINS SHOULD KEEP OUR EAST COOLER...ESPECIALLY AFTER A COLD
MORNING. HAVE ADJUSTED TEMPS IN OUR EAST DOWN SOME PER MODEL
CONSENSUS.
IT APPEARS SATURDAY WILL BE THE WARMEST DAY OF THE EXTENDED PERIOD
AS THE RIDGE AXIS SHIFTS FURTHER EAST AND BEGINS TO FLATTEN IN
RESPONSE TO NEXT SHORTWAVE OFF THE PACIFIC. MODELS HAVE TRENDED
SLOWER WITH A COLD FRONTAL PASSAGE...IT NOW LOOKS TO OCCUR
SATURDAY NIGHT...AND THIS WILL SET THE STAGE FOR A DRY/WINDY AND
VERY WARM SATURDAY. GIVEN SUCH ANOMALOUSLY HIGH HEIGHTS AND THE
STRONG DOWNSLOPE PREFRONTAL FLOW HAVE RAISED EXPECTED HIGHS
FURTHER INTO THE 70S.
MODEST COOL DOWN IN STORE FOR SUNDAY BEHIND THE CLIPPER SYSTEM...
WHICH MAY BRING A LITTLE SHOWER ACTIVITY SATURDAY NIGHT INTO
SUNDAY. IT IS LOOKING MORE AND MORE LIKE MARCH WILL END ON A WARM
NOTE WITH UPPER RIDGING EXPECTED TO PERSIST THRU EARLY NEXT WEEK.
JKL
&&
.AVIATION...
PATCHY FOG AND LOCAL IFR TO VLIFR CONDITIONS WILL IMPACT FAR
SOUTHEAST MONTANA NEAR KBHK THRU 15Z THIS MORNING.
MOSTLY CLEAR SKIES EARLY TODAY WILL GIVE WAY TO A RAPID INCREASE
IN CLOUD COVER THIS MORNING AS A DISTURBANCE APPROACHES FROM THE
WEST. SCATTERED SHOWERS WILL DEVELOP THIS AFTERNOON AND EVENING...
PRODUCING LOCAL MVFR CONDITIONS...AND AN ISOLD TSTM IS ALSO
POSSIBLE. HEAVIEST PRECIPITATION AND GREATEST POTENTIAL FOR SUB-
VFR WILL BE IN OUR EAST NEAR KMLS AND KBHK TONIGHT. MOUNTAINS WILL
BECOME OBSCURED IN SNOW SHOWERS. GUSTY WEST WINDS WILL DEVELOP
BEHIND A PACIFIC COLD FRONT LATE THIS AFTERNOON AND EVENING...WITH
GUSTS UP TO 30 KTS POSSIBLE. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
TDY TUE WED THU FRI SAT SUN
-------------------------------------------------------
BIL 064 039/055 031/048 034/051 032/070 046/077 042/061
2/W 54/W 43/W 32/W 10/B 01/N 22/W
LVM 058 031/048 028/048 034/055 035/070 047/072 041/061
6/T 55/W 53/W 22/W 10/N 01/N 22/W
HDN 068 037/058 029/048 032/051 028/070 039/079 038/063
2/W 53/W 33/W 32/W 10/B 01/N 22/W
MLS 068 039/055 027/045 026/048 026/066 039/076 036/060
2/T 62/W 12/W 22/W 10/B 01/N 21/B
4BQ 070 037/056 027/045 026/047 026/064 038/078 037/060
3/T 63/W 12/W 23/W 10/B 01/N 21/B
BHK 064 036/051 024/039 020/041 021/058 035/074 033/055
1/B 74/W 12/J 22/J 10/B 01/N 21/B
SHR 066 035/053 027/045 028/048 026/065 038/078 039/060
2/W 54/W 44/W 43/W 20/B 00/B 22/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
431 AM EDT MON MAR 23 2015
.SYNOPSIS...
THERE WILL BE A FEW SNOW SHOWERS SOUTH OF LAKE ONTARIO THIS MORNING
OTHERWISE IT WILL SIMPLY BE DRY AND COLD WITH TEMPERATURES RUNNING
ABOUT 20 DEGREES BELOW NORMAL. HIGH PRESSURE WILL PROVIDE DRY
WEATHER THROUGH TUESDAY BEFORE A STRONG WARM FRONT CROSSES THE AREA
WEDNESDAY WITH RAIN SHOWERS. THIS FRONT WILL USHER IN MUCH WARMER
TEMPERATURES FOR THE MIDDLE OF THE WEEK BEFORE MORE COLD ARRIVES BY
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE PIVOTING AROUND THE WESTERN FRINGE OF AN UPPER LEVEL
TROUGH ACROSS EASTERN CANADA WILL PUSH A WEAK COLD FRONTAL BOUNDARY
ACROSS THE REGION THROUGH THIS MORNING. SURFACE CONVERGENCE ALONG
THIS BOUNDARY SHOULD ENHANCE AND PROVIDE A FOCUS FOR OTHERWISE
LIMITED LAKE EFFECT SNOW SHOWER ACTIVITY. THE HRRR HAS THIS BOUNDARY
WELL RESOLVED WITH IT EXPECTED TO DROP SOUTH OF LAKE ONTARIO THROUGH
12Z BEFORE FALLING APART THIS MORNING. THIS IS A SIMILAR SCENARIO
TO YESTERDAY EXPECT RADAR/SATELLITE SHOWS MUCH LESS MOISTURE THAN
YESTERDAY SO SNOWFALL AMOUNTS SHOULD BE LIMITED WITH STEADIER
SNOWS ONLY PRODUCING AN INCH OR SO IN SOME LOCATIONS.
OTHERWISE...HIGH PRESSURE WILL TAKE CONTROL WITH DRY AIR MIXING IN
WITH SHALLOW LAKE MOISTURE LEADING TO INCREASING SUNSHINE THIS
AFTERNOON. TEMPERATURES WILL STILL BE WELL BELOW NORMAL WITH HIGHS
ONLY IN THE 20S IN MOST LOCATIONS.
NAM/RGEM/GFS MODEL CONSENSUS DROPS A WEAK SHORTWAVE TO OUR SOUTH
TONIGHT AND THIS MAY CLIP THE REGION WITH SOME CLOUDS BUT OTHERWISE
SHOULD HAVE LITTLE IMPACT ON OUR SENSIBLE WEATHER. WITH COLD AIR IN
PLACE...AND CALM WINDS EXPECT THERE WILL BE PRETTY GOOD RADIATIONAL
COOLING TONIGHT. HEDGED WITH COOLER GUIDANCE WITH LOWS 10 TO 15
SOUTH OF LAKE ONTARIO...BUT IN THE SINGLE DIGITS TO NEAR ZERO IN THE
NORTH COUNTRY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
HIGH PRESSURE AT THE SURFACE WILL PASS ACROSS OUR REGION TUESDAY
WHILE ALOFT AN UPPER LEVEL SHORTWAVE WILL BE RIPPLING THROUGH THE
MAIN WESTERLY FLOW. THESE LOWER 700/850 HPA HEIGHTS ALOFT MAY ALLOW
FOR A FEW DIURNALLY DRIVEN CU TO FORM EARLY TUESDAY...BUT BECOME
FEWER IN NUMBER THROUGH THE AFTERNOON HOURS FOLLOWING THE PASSAGE OF
THE SHORTWAVE AND BUILDING HEIGHTS FROM THE WEST.
THIS UPPER LEVEL RIDGE WILL PASS OVER THE REGION TUESDAY NIGHT.
CLEAR SKIES AND LIGHT WINDS WILL BRING FAVORABLE RADIATIONAL COOLING
CONDITIONS DURING THE EVENING HOURS WITH TEMPERATURES DROPPING DOWN
INTO THE 20S. THEN A SOUTHERLY FLOW BEHIND THE DEPARTING AREA OF
HIGH PRESSURE WILL START TO BRING MILDER TEMPERATURES NORTHWARD.
FIRST TO BEGIN TO WARM WILL BE AREAS NEAR THE LAKE ERIE SHORELINE.
THIS MILDER AIR WILL PUSH EASTWARD BUT NOT BEFORE AREAS EAST OF LAKE
ONTARIO BOTTOM OUT IN THE TEENS OVERNIGHT.
THIS RETURN OF MILD SOUTHERLY FLOW WILL ALSO BRING INCREASING
AMOUNTS OF MOISTURE NORTHWARD. FLOW FROM BOTH THE ATLANTIC AND GULF
OF MEXICO WILL INCREASE MOISTURE THROUGH THE NIGHT OVER THE OHIO
VALLEY. AS A WARM FRONT NEARS THE REGION FROM THE OHIO VALLEY A RAIN
OR LOWER CHANCE...WET SNOW SHOWER IS POSSIBLE JUST BEFORE DAYBREAK
WEDNESDAY MORNING.
WEDNESDAY THROUGH THURSDAY WILL BE ACTIVE FOR OUR REGION AS ABOVE
NORMAL WARMTH...AND POSSIBLY TWO WAVES OF RAIN PASS OVER THE REGION.
SYNOPTICALLY...A SHARP SHORTWAVE WILL BE FOUND WEDNESDAY MORNING
OVER THE MIDWEST...WITH A SEVERAL ADDITIONAL SHORTWAVES OVER THE
NORTHERN PLAINS AND NORTHERN ROCKIES.
AT THE SURFACE WEDNESDAY AN AREA OF LOW PRESSURE THAT WILL REMAIN
EITHER STEADY OR SLIGHTLY FILLING...WILL ADVANCE FROM NEAR THE
SOUTHERN SHORELINE OF LAKE MICHIGAN NORTHEASTWARD TOWARDS THE SAINT
LAWRENCE VALLEY WEDNESDAY NIGHT. THIS FIRST SURFACE LOW WILL BRING
HIGH CONFIDENCE OF A PERIOD OF MAINLY LIGHT RAIN PASSING ACROSS THE
REGION. ISENTROPIC UPGLIDE...COMBINED WITH STRONG LOW LEVEL
CONVERGENCES ON THE NOSE OF A 65 KNOTS LLJ WILL BRING RAIN THROUGH
THE MORNING HOURS ACROSS WNY. ACTIVITY WILL THEN EXPAND NORTHWARD
ACROSS THE FINGER LAKES AND EASTERN LAKE ONTARIO REGION THROUGH THE
AFTERNOON HOURS.
OVERALL RAINFALL FROM THIS WEDNESDAY SYSTEM LOOKS TO RANGE FROM A
TENTH UPWARD TO A THIRD OF AN INCH.
BEHIND THE PERIOD OF RAIN WEDNESDAY SCATTERED RAIN SHOWERS WILL
CONTINUE THROUGH THE AFTERNOON AND EVENING HOURS. THERE MAY EVEN BE
A FEW BREAKS IN THE CLOUDS SOUTH OF LAKE ONTARIO AS DRIER AIR WITHIN
THE WARM SECTOR OF THE STORM SYSTEM REACHES THE REGION. WEDNESDAY
WILL ALSO BE BREEZY WITH THE TIGHTENING PRESSURE GRADIENT AND STRONG
FLOW JUST A FEW THOUSAND FEET ABOVE THE SURFACE. WINDS MAY GUST
UPWARDS TO 20 TO 30 KNOTS WEDNESDAY AFTERNOON...THOUGH WITH THE AREA
OF LOW PRESSURE STEADY IN ITS MSLP...AND NOT DEEPENING IN
ADDITION TO THE WARM AIR ADVECTION PATTERN CREATING A STEEP LOW
LEVEL INVERSION...STRONG...ADVISORY LEVEL WIND GUSTS WILL LIKELY NOT
MIX DOWN TO THE SURFACE.
RELATIVE WEAK RIDGING WILL BE FOUND OVER THE REGION WEDNESDAY NIGHT
AS THE FIRST SHORTWAVE DEPARTS EASTWARD...AND A SECOND AND DEEPER
TROUGH OF LOW PRESSURE NEARS US FROM THE WEST. IT IS THIS SECOND
TROUGH RIDING OVER A LOW LEVEL BAROCLINIC ZONE THAT WILL DEVELOP
ANOTHER SURFACE WAVE OF LOW PRESSURE OVER THE MIDWEST WEDNESDAY
NIGHT.
THERE IS STILL SOME MODEL UNCERTAINTY IN THE TRACK OF THIS SECOND
AREA OF LOW PRESSURE. THE 00Z/23 GFS TAKES A DEEPENING AREA OF LOW
PRESSURE OVER THE CWA...WHILE THE TRACK OF THE 00Z/23 ECMWF LOW IS
JUST A SHADE FARTHER EASTWARD THAN THE GFS. THIS SLIGHTLY EASTWARD
TRACK ON THE ECMWF WOULD MEAN HIGHS THURSDAY WILL NOT BE AS WARM AS
THE GFS OUTPUT...THOUGH BOTH MODELS ARE INDICATING THAT A GREATER
RAINFALL EVENT THAN WEDNESDAY IS POSSIBLE. WITH THERE STILL BEING
SOME UNCERTAIN TO THE TEMPERATURES...DEWPOINTS AND RAINFALL MIDWEEK
WILL HOLD OFF ON ANY FLOOD HEADLINES...THOUGH WILL MAINTAIN THE
MENTION OF POSSIBLE FLOODING CONCERNS IN THE HWO PRODUCT.
HIGHS ON WEDNESDAY AND THURSDAY WILL REACH INTO THE 40S...AND
POSSIBLY WELL INTO THE LOWER 50S SOUTH OF LAKE ONTARIO ON EITHER
DAY. OVERNIGHT LOWS WEDNESDAY NIGHT WILL REMAIN ABOVE NORMAL WITH
LOWS IN THE UPPER 30S TO LOWER 40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
BEHIND THE MID-WEEK WEATHER SYSTEM...THE END OF THE WORK WEEK INTO
THE WEEKEND WILL SEE BELOW NORMAL TEMPERATURES AND THE POTENTIAL FOR
SOME LAKE EFFECT SNOW SHOWERS SOUTHEAST OF LAKE ONTARIO. AS THE
UPPER-LEVEL TROUGH WORKS ACROSS NEW YORK STATE...AND THE SURFACE
HIGH PRESSURE MOVES IN...COLD 850 MB TEMPERATURES INTO THE MINUS
TEENS CELSIUS...WILL MEAN HIGH TEMPERATURES BACK INTO THE 20S AND
30S. NORTHWESTERLY FLOW AS THE SURFACE HIGH BUILDS IN...ALONG WITH
THE COLDER TEMPERATURES WILL LIKELY YIELD A LIMITED LAKE RESPONSE
OFF LAKE ONTARIO. GLOBAL MODELS ARE IN GOOD AGREEMENT ON THE NEXT
CLIPPER SYSTEM IMPACTING THE STATE BY LATE SUNDAY.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
A WEAK FRONT AND ASSOCIATED CONVERGENCE BOUNDARY WILL DROP ACROSS
THE REGION THROUGH 12Z. THIS MAY BRING A BRIEF IFR/MVFR SNOW SHOWERS
SOUTH OF LAKE ONTARIO. HIGH PRESSURE WILL BUILD IN LATE MORNING ON
WITH MAINLY VFR CONDITIONS EXPECTED THIS AFTERNOON AND EVENING. A
WEAK SHORTWAVE MAY RESULT IN A MVFR CLOUD DECK LATE TONIGHT...BUT
FOR THE MOST PART EXPECT THIS TO BE SCATTERED IN NATURE.
OUTLOOK...
TUESDAY...VFR.
WEDNESDAY...AREAS OF MVFR IN RAIN SHOWERS.
THURSDAY...MVFR/IFR WITH RAIN.
FRIDAY...MVFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
MODERATE NORTHWESTERLIES WILL DIMINISH THROUGH THIS MORNING AS HIGH
PRESSURE GRADUALLY BUILDS ACROSS THE REGION. THIS SHOULD ALLOW THE
SMALL CRAFT HEADLINES TO BE DROPPED TODAY. HIGH PRESSURE WILL THEN
SETTLE DIRECTLY ACROSS THE LOWER LAKES TONIGHT AND TUESDAY AND BRING A
PERIOD OF LIGHT WINDS AND QUIET WEATHER.
&&
.HYDROLOGY...
MODEL GUIDANCE CONTINUES TO SUGGEST THAT THERE WILL BE A WARM UP
MID-WEEK. THERE WILL BE TWO WAVES OF LOW PRESSURE. WESTERN NEW
YORK IS LIKELY TO BE ON THE WARM SIDE OF THE FIRST AND WEAKER
WAVE...BUT THERE IS MODEL DISAGREEMENT ON THE TRACK OF THE SECOND
WAVE. THIS IS IMPORTANT BECAUSE IT WOULD PROBABLY BE THE SECOND
WAVE THAT WOULD HAVE THE GREATEST POTENTIAL TO CAUSE FLOODING.
MMEFS ENSEMBLE GUIDANCE SUGGESTS AROUND A 30 PERCENT CHANCE FOR FLOODING
ON MOST OF THE BUFFALO CREEKS AND SOME FORECAST POINTS IN THE
GENESEE AND ALLEGHENY BASINS. THIS DOES NOT TAKE INTO ACCOUNT THAT
THERE ARE ICE JAMS IN PLACE ON SOME CREEKS WHICH COULD RESULT IN
ICE JAM FLOODING IF FLOWS INCREASE RAPIDLY.
HYDROLOGIC CONDITIONS ARE DISCUSSED IN THE ESF PRODUCT...AND THE
RISK FOR FLOODING MID TO LATE WEEK IS DISCUSSED IN THE HAZARDOUS
WEATHER OUTLOOK (HWO). IF THERE IS GOING TO BE FLOODING DUE TO
SNOW MELT THIS SPRING...THIS WILL PROBABLY HAVE TO BE THE SYSTEM
TO DO IT FOR THE BUFFALO CREEKS...GENESEE...AND ALLEGHENY BASINS.
IF FORECAST CONFIDENCE INCREASES IT IS POSSIBLE THAT FLOOD WATCHES
WILL BE NEEDED FOR SOME AREAS IN THE LATE WEDNESDAY THROUGH FRIDAY
TIMEFRAME.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LOZ042-
043.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...THOMAS
LONG TERM...CHURCH
AVIATION...APFFEL
MARINE...APFFEL
HYDROLOGY...APFFEL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
350 AM EDT MON MAR 23 2015
.SYNOPSIS...
A SERIES OF WEAK AREAS OF LOW PRESSURE WILL MOVE EAST ALONG A STALLED
FRONT SOUTH OF THE AREA THROUGH TUESDAY. HIGH PRESSURE WILL EXTEND
INTO THE AREA FROM THE NORTH THROUGH MIDWEEK. A STRONG COLD FRONT
WILL APPROACH FROM THE WEST THURSDAY AND MOVE THROUGH FRIDAY.
LOW PRESSURE WILL MOVE ACROSS SOUTHEAST OF THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 330 AM MONDAY...LIGHT RAIN CONTINUES ALONG THE SOUTHERN
COASTAL SECTIONS OF EASTERN NORTH CAROLINA...WITH AMOUNTS OF UP TO
ONE QUARTER INCH THUS FAR. DESPITE RETURNS ON RADAR...THE SUBCLOUD
LAYER HAS REMAINED TO DRY FOR MUCH MORE THAN SPRINKLES TO EACH THE
GROUND OVER AREAS FURTHER NORTH THIS MORNING. THE LATEST 3KM HRRR
AND RAP MODELS SHOW THE BULK OF PRECIPITATION WILL REMAIN CONFINED
TO THE COASTAL SECTIONS WITH A GOOD GRADIENT OF RAIN ACROSS THE
REGION. WILL HAVE LIKELY POPS ALONG THE SOUTH COAST...TAPERING TO
CHANCE OVER THE FAR NORTHERN AREAS...THROUGH THE MORNING HOURS.
THE HRRR SHOWS THE BULK OF THE RAINFALL SHOULD BE OFFSHORE BY 18Z
OR 19Z THIS AFTERNOON. IT WILL BE A CHILLY START TO THE WORKWEEK
WITH HIGHS TEMPERATURES LINGERING IN THE UPPER 40S OVER THE
NORTHERN OUTER BANKS WITH LOW/MID 50S ELSEWHERE...EXCEPT A FEW
UPPER 50S OVER THE FAR SOUTHWESTERN COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 330 AM MONDAY...LOW PRESSURE WILL MOVE WELL EAST OF THE AREA
TONIGHT AS COOL HIGH PRESSURE BUILDS SOUTH FROM CANADA. EXPECT A
VEIL OF MID CLOUDS TO HANG AROUND...BUT TEMPERATURES WILL STILL BE
CHILLY FOR LATE MARCH WITH LOWS RANGING IN THE MID/UPPER 30S
INLAND TO THE LOWER 40S OUTER BANKS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 330 AM MON...LONG TERM PERIOD WILL FEATURE VERY
CHANGEABLE WEATHER PATTERN TYPICAL OF EARLY SPRING WITH LARGE
VARIATION IN TEMPERATURES AND AN UNSETTLED PATTERN.
MAINLY DRY CONDITIONS TUE NIGHT INTO WED WITH HIGH PRES TO THE
NORTHEAST REESTABLISHING ITSELF ACROSS E NC WITH ZONAL FLOW ALOFT.
SOME MODERATION IN TEMPS FOR TUE THOUGH STILL BELOW CLIMO WITH HIGHS
NEAR 50 NORTHEAST TO NEAR 60 SOUTHWEST UNDER PARTLY SUNNY SKIES.
LOWS NEAR CLIMO TUE NIGHT WITH READINGS IN THE 40S. CONTINUED
PREVIOUS FCST TREND WITH PCPN HOLDING OFF DURING THE DAY WED AS
RETURN FLOW BECOMES SOUTHEAST LATE IN THE DAY THOUGH LOW LEVELS
STILL DRY WITH JUST AN INC IN CLOUD COVER EXPECTED. HIGHS EXPECTED
NEAR 70 AWAY FROM THE COAST WITH 50S ON THE OUTER BANKS WITH
CONTINUED NORTHEAST BREEZE KEEPING IT COOLER HERE.
INC CHANCES FOR RAIN SHOWERS WED NIGHT AS RETURN SSW FLOW
STRENGTHENS AND RAPID INC IN LOW LEVEL MOISTURE ENSUES. SHORTWAVE
ENERGY PIVOTING AROUND LONG WAVE CENTRAL CONUS TROUGH WILL AID IN
UPR SUPPORT FOR SCT TO NUMEROUS RAIN SHOWERS.
FOR THUR...WARM AND HUMID DAY EXPECTED WITH BUILDING LOW LEVEL
THICKNESSES AND RESPONDING INC TEMPS AND DEWPOINTS EXPECTED AHEAD OF
APPROACHING STRONG COLD FRONT AND AFOREMENTIONED LONG WAVE TROUGH.
SFC INSTABILITY WILL BE PRESENT WITH PARTLY SUNNY SKIES EXPECTED
...ALONG WITH SUFFICIENT DEEP LAYER SHEAR FOR THE POSSIBILITY OF
ORGANIZED THUNDER. HOWEVER...UPR SUPPORT WILL REMAIN WELL WEST OF
THE AREA AS POSTITVELY TILTED TROUGH IS SLOW TO MAKE HEADWAY TOWARDS
E NC...SO THREAT FOR SEVERE IS MARGINAL AT THIS TIME. HIGHS WILL
EASILY CLIMB INTO THE 70S...POSSIBLY HIGHER IF MORE SUNSHINE BREAKS
OUT. PRECIP THREAT WILL CONTINUE INTO THUR NIGHT AS 23/00Z
GFS/ECM/CMC IN GENERAL AGREEMENT ON A THUR NIGHT/FRI MORNING FRONTAL
PASSAGE.
FOR FRIDAY...POSITIVELY TILTED UPR TROUGH REMAINS WEST OF THE AREA
DESPITE THE SFC FRONTAL PASSAGE. MODELS INDICATE MORE SHORTWAVE
ENERGY ALOFT PRODUCING CHANCES FOR PRECIP THROUGH THE DAY AND WILL
RETAIN THE CHANCE POPS. TEMPS WILL BE NEAR CLIMO WITH HIGHS
GENERALLY IN THE 60S...WITH COOLER 50S OBX UNDER NORTHEAST SFC FLOW.
FRI NIGHT THROUGH SAT THERE IS DISAGREEMENT WITH RESPECT TO UPR
SUPPORT AS TROUGH AXIS WORKS THROUGH E NC. DETERMINISTIC GFS/CMC
CONTINUE WITH A WETTER SOLN WITH A COLD RAIN POSSIBLY MIXING WITH A
FEW SNOW SHOWERS...THOUGH LATEST 23/00Z ECMWF HAS A DRIER TREND.
WILL CONTINUE PREVIOUS CHANCE POPS AS WOULD LIKE TO SEE MORE
CONSISTENCY FROM ECMWF BEFORE MAKING LARGE SCALE CHANGES.
SUNDAY WILL BE QUITE COLD FOR LATE MARCH WITH TEMPS SOME 15-20
DEGREES BELOW CLIMO AND POSSIBLE FROST OR FREEZING CONDITIONS FOR E
NC. GROWING SEASON WILL BEGIN ACROSS ALL OF EASTERN NC ON MARCH 28.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 06Z TUESDAY/...
AS OF 115 AM MONDAY...DESPITE AN ACTIVE RADAR...THE SUB CLOUD
LAYER IS RATHER DRY AND CEILINGS REMAIN HIGH AS IT WILL TAKE WHILE
TO MOISTEN THE COLUMN. ALL GUIDANCE SHOWING VFR CONDITIONS TO
PREVAIL BUT STILL BELIEVE THERE WILL BE AT LEAST A PERIOD OF MVFR
CEILINGS AT THE SOUTHERNMOST TAF SITE DURING THE MORNING HOURS AS
A STEADY LIGHT RAIN FALLS. LOWER CLOUDS WILL MIX OUT AS DRIER AIR
ADVECTS INTO THE AREA LATE MONDAY MORNING WITH A RETURN TO VFR
EXPECTED ALL LOCATIONS DURING THE AFTERNOON. GUSTY NE WINDS
DEVELOP BY MIDDAY MONDAY AS DEEPENING SFC LOW PRESSURE PASSES
OFFSHORE.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...VFR CONDITIONS WILL DOMINATE TUE AND WED. NEXT
CHANCE FOR RAIN SHOWERS AND SUB VFR CONDITIONS WILL BE WED NIGHT
INTO THUR AS MOISTURE STREAMS NORTHWARD AHEAD OF STRONG COLD FRONT
SET TO PASS THROUGH BY FRIDAY MORNING. S TO SW WINDS WILL BE GUSTY
ON THURSDAY.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 340 AM MONDAY...GRADIENT WILL INCREASE DRAMATICALLY OVER THE
NEXT FEW HOURS BETWEEN LOW PRESSURE PASSING TO OUR SOUTH AND
CANADIAN HIGH PRESSURE BUILDING DOWN FROM THE NORTH. EXPECT
NORTHEAST WINDS TO INCREASE TO 20 TO 25 KNOTS OVER THE COASTAL
WATERS WITH A PERIOD OF 25 TO 30 KNOT WINDS POSSIBLE OVER THE
CENTRAL WATERS THROUGH THE MID TO LATE MORNING HOURS. ON THE
SOUNDS...WINDS WILL GENERALLY BE 15 TO 20 KNOTS BUT DO EXPECT
FREQUENT GUSTS TO 25 KNOTS THIS MORNING ESPECIALLY. PER LATEST
LOCAL NWPS/SWAN MODEL...SEAS WILL BUILD TO AS HIGH AS 7 OR 8 FEET
THROUGH THE LATE MORNING AND AFTERNOON HOURS...ESPECIALLY CENTRAL
AND NORTHERN WATERS. ONLY CHANGE TO ADVISORIES WAS TO EXTEND FAR
SOUTHERN WATERS INTO TUESDAY EVENING WITH SEAS REMAINING ELEVATED.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...THE PRESSURE GRADIENT LOOSENS ON TUE
WITH SCA CONDITIONS ENDING. HIGH PRESSURE WILL CONTINUE TO PRODUCE
NORTHEAST WINDS IN THE 15-20 KT RANGE THROUGH TUE NIGHT. THE HIGH
WILL MOVE OFF THE COAST ON WEDNESDAY AND WINDS WILL VEER TO
SOUTHEAST LATE IN THE AFTERNOON. THE FLOW WILL CONTINUE TO VEER TO
SOUTH WEDNESDAY NIGHT AND THURSDAY AS THE HIGH MOVES EAST AND A COLD
FRONT APPROACHES FROM THE WEST. SCA CONDITIONS WILL LIKELY REDEVELOP
BY LATE WED NIGHT OR THURSDAY AS SOUTHERLY WINDS STRENGTHEN AND SEAS
BUILD ABOVE 6 FT. FRONT WILL PASS OFF THE COAST FRI MORNING WITH
WINDS TURNING NORTHERLY. THE NORTH WINDS WILL STRENGTHEN ON SATURDAY
AS STRONG COLD AIR ADVECTION MOVES INTO THE E NC WATERS WITH GUSTY
NORTH WINDS AND HIGH SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR AMZ130-
131-150.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...CTC
LONG TERM...TL
AVIATION...CTC/TL
MARINE...CTC/TL
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1253 AM CDT MON MAR 23 2015
.AVIATION.../06Z TAF CYCLE/
VFR SKC CONDITIONS ONGOING NOW THROUGH 08-09Z WITH EXPECTED FALLING
CATEGORIES FOR KAUS/KSSF/KSAT TERMINALS THEREAFTER THROUGH 15Z.
COMBINATION OF PATCHY FOG AND LOW CEILINGS WILL LIKELY OCCUR WITH
A VARIANCE OF MVFR TO AS LOW AS LIFR WHERE PATCHY LOCALIZED DENSE
FOG COULD OCCUR. FEEL MAJORITY OF 09-15Z TIME FRAME WILL BE LOW
END MVFR AS LOW STRATUS DEVELOPS OVER SOUTH CENTRAL TEXAS. HAVE
PLACED TEMPO GROUPS FOR POSSIBLE THICKER FOG AND LOWER CIGS PER
BULLISH NAM SOUNDINGS AND HRRR OUTPUT. KDRT WILL STAY VFR SKC
THROUGH THE NIGHT AND REST OF MONDAY. CENTRAL SITES WILL RECOVER
THROUGH MID MORNING AND BE VFR BY 17-19Z WITH KSAT/KSSF LIKELY
HOLDING ON THE LONGEST. EXPECT ANOTHER POSSIBLE MVFR/IFR CEILINGS
TO DEVELOP TUESDAY MORNING. SURFACE WINDS WILL BE NEAR CALM NOW
THROUGH 12Z AND REMAIN 5-10 KT THROUGH THE DAY WHILE VEERING FROM
THE NE TO THE SE BY LATE MONDAY INTO EARLY TUESDAY. /ALLEN/
&&
PREV DISCUSSION... /ISSUED 906 PM CDT SUN MAR 22 2015/
UPDATE...
FORECAST REMAINS ON TRACK FOR NOW. UPDATE INCLUDE A MENTION OF
DENSE FOG FOR THE NERN HALF OF THE AREA GIVEN A DEVELOPING FAVORABLE
LOW LEVEL WIND FORECAST AT DAYBREAK AND THE EXISTING SOAKED
SOILS.
PREV DISCUSSION... /ISSUED 252 PM CDT SUN MAR 22 2015/
SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...
A DRY WEATHER PATTERN IS IN STORE FOR THE NEXT FEW DAYS WITH A
WARMING TREND EXPECTED THROUGH MID WEEK. THE UPPER LEVEL TROUGH
THAT BROUGHT MODERATE TO HEAVY RAIN OVER THE REGION THE PAST FEW
DAYS IS NOW PUSHING TO THE EAST AND MOVING INTO THE MISSISSIPPI
VALLEY. AS IT DOES THAT...DRY NORTHWEST TO WEST FLOW WILL SPREAD
ACROSS SOUTH CENTRAL TEXAS AND PRODUCE FAIR WEATHER DAYS.
HOWEVER...THERE IS A VERY SLIGHT CHANCE FOR LIGHT SHOWERS THIS
AFTERNOON ACROSS PARTS OF THE SOUTHEAST OR EAST OF INTERSTATE 35
AS A WEAK ASCENT/OMEGA AREA PUSHES OVER THAT REGION. EXPECT PARTLY
CLOUDY SKIES ACROSS MUCH OF THE AREA TONIGHT INTO MONDAY WITH
CLEAR SKIES ALONG THE RIO GRANDE PLAINS. AT THE SURFACE...A HIGH
PRESSURE SYSTEM CENTERED ACROSS THE ARKLATEX IS FORECAST TO PUSH
TO THE EAST AND BRING SOUTHERLY WINDS TO THE REGION. DUE TO THE
RECENT RAINS AND WET SOILS WITH DEWPOINTS IN THE UPPER 50S AND
LOWER 60S ACROSS THE COASTAL PLAINS OVERNIGHT...LIGHT PATCHY FOG
IS ANTICIPATED FOR AREAS ALONG AND EAST OF INTERSTATE 35 OVERNIGHT
THROUGH EARLY MONDAY MORNING. OVERNIGHT LOWS WILL RANGE FROM THE
UPPER 40S ACROSS THE HILL COUNTRY TO MID 50S ACROSS THE COASTAL
PLAINS.
LONG TERM (TUESDAY THROUGH SUNDAY)...
FAIR WEATHER CONDITIONS ARE EXPECTED ACROSS SOUTH CENTRAL TEXAS
THROUGH WEDNESDAY. BY WEDNESDAY NIGHT INTO THURSDAY...AN UPPER
LEVEL DISTURBANCE IS FORECAST TO PUSH ACROSS THE AREA WHILE A
COLD FRONT MOVES THROUGH THE REGION. BOTH GFS AND EURO MODELS
BRING THE FRONTAL BOUNDARY AROUND 2 AM THURSDAY ACROSS THE HILL
COUNTRY WITH RAIN CHANCES INCREASING OVERNIGHT INTO THURSDAY.
ALSO...THESE MODELS ARE SHOWING SIGNS OF SERRANIA DEL BURRO
MOUNTAINS STORMS DEVELOPING WEDNESDAY AFTERNOON AND THEN MOVING
ACROSS THE SOUTHERN EDWARDS PLATEAU IN THE EVENING. ONCE THE UPPER
LEVEL SUPPORT PUSHES TO THE EAST AND THE COLD FRONT CONTINUES TO
MOVE SOUTH AND OVER THE NORTHWEST GULF WATERS...WEATHER CONDITIONS
ARE EXPECTED TO IMPROVE LATE THURSDAY INTO FRIDAY WITH DRY
CONDITIONS ANTICIPATED THROUGH SUNDAY OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 78 57 80 59 78 / 0 0 0 - -
AUSTIN BERGSTROM INTL AIRPORT 77 55 80 57 78 / 0 0 0 - -
NEW BRAUNFELS MUNI AIRPORT 79 56 79 57 78 / 0 0 0 - -
BURNET MUNI AIRPORT 77 58 80 59 78 / 0 0 0 - -
DEL RIO INTL AIRPORT 86 61 86 62 83 / 0 0 0 - -
GEORGETOWN MUNI AIRPORT 76 57 79 59 77 / 0 0 0 - -
HONDO MUNI AIRPORT 81 57 82 58 80 / 0 0 0 - -
SAN MARCOS MUNI AIRPORT 77 56 79 57 78 / 0 0 0 - -
LA GRANGE - FAYETTE REGIONAL 77 56 80 59 78 / 0 0 0 - -
SAN ANTONIO INTL AIRPORT 80 58 81 59 78 / 0 0 0 - -
STINSON MUNI AIRPORT 80 57 82 58 79 / 0 0 0 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...15
SYNOPTIC/GRIDS...04
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1140 PM CDT SUN MAR 22 2015
.AVIATION...
CONCERNS...AREAS OF FOG WILL DEVELOP OVERNIGHT...WITH POSSIBLE
IFR/LIFR CONDITIONS BEFORE DAYBREAK THAT WILL CONTINUE THROUGH
15-16Z.
METROPLEX TAF SITES...
WITH CLEAR SKIES...LIGHT WINDS AND A MOIST GROUND...AREAS OF
SHALLOW FOG WILL DEVELOP OVERNIGHT. SOME LOCALLY DENSE FOG IS
POSSIBLE. FOR NOW...HAVE INDICATED 4SM BR AROUND 08Z AND 1SM BR BY
11Z. FOR THE 11-14Z PERIOD...HAVE SHOWN TEMPO 1/2SM FG VV002 OR
OVC002...BUT WOULD NOT BE SURPRISED IF THEY GO DOWN TO 1/4SM FG
VV001 OR OVC001. THE FOG SHOULD BE SHALLOW AND AN IMPROVEMENT TO
VFR SHOULD OCCUR AROUND OR SHORTLY AFTER 16Z. SOUTH FLOW WILL
CONTINUE THROUGH THE NEXT 36 HOURS.
WACO...
EXPECT A SIMILAR SCENARIO AT WACO...WITH AREAS OF FOG DEVELOPING
AROUND 06Z...AND VISIBILITIES DROPPING TO 1SM BY 09Z. HAVE
INDICATED A TEMPO 1/2SM FG OVC002 FOR THE 10-14Z PERIOD WITH AN
IMPROVEMENT TO VFR 16-17Z. LIGHT AND VARIABLE WINDS OVERNIGHT WILL
BECOME SOUTHEAST 5 TO 8 KNOTS BY 15Z MONDAY.
58
&&
.UPDATE...
SKIES HAVE CLEARED...AND WINDS HAVE SUBSIDED. MANY LOCATIONS HAVE
ALREADY DIPPED INTO THE 50S...RAPIDLY APPROACHING DEW POINTS.
FOLLOWING A WIDESPREAD RAINFALL EVENT...THIS WOULD APPEAR THE
PERFECT RECIPE FOR FOG. HOWEVER...GUIDANCE IS A BIT GUN-SHY. THE
NAM PERFECT PROG IS THE MOST BULLISH...BLANKETING NEARLY THE
ENTIRE CWA IN DENSE FOG...BUT THE CORRESPONDING MOS IS FREE OF ANY
SIGNIFICANT RESTRICTIONS TO VISIBILITY. THE RAP AND HRRR INDICATE
SOME DENSE FOG...BUT NEITHER IS INCLINED FOR IT TO BE WIDESPREAD.
THE 00Z FWD RAOB SHOWS THAT THE MOIST LAYER IMMEDIATELY ADJACENT
TO THE SURFACE IS INCREDIBLY THIN. ALTHOUGH THE WINDS ARE
PROJECTED TO REMAIN LIGHT WITHIN A MILE OF THE SURFACE...EASILY
ASSURING ADEQUATE RADIATIONAL COOLING...EVEN A LIGHT BREEZE AT THE
SURFACE MAY BE ENOUGH TO ENTRAIN DRIER AIR JUST A FEW HUNDRED FEET
OFF THE DECK.
WHERE WINDS ARE CALM...EXPECT DEW WILL BEGIN TO FORM AS GROUND
TEMPS COOL MORE RAPIDLY THAN THE 2-METER TEMPS INDICATE. SHALLOW
FOG WILL THEN GRADUALLY DEVELOP. THE LOWEST VISIBILITIES WILL
FAVOR LOW-LYING AREAS...BODIES OF WATER...AND LOCATIONS WHERE THE
HEAVIEST RAINFALL AMOUNTS OCCURRED. BUT EVEN IN THESE AREAS...THE
DEPTH OF THE FOG WILL LIKELY BE LESS THAN A FEW HUNDRED FEET. IT
MAY TAKE ANOTHER SEVERAL HOURS (WELL AFTER MIDNIGHT) FOR ANY DENSE
FOG TO DEVELOP. AT THIS TIME...DO NOT EXPECT DENSE FOG WILL BE
WIDESPREAD ENOUGH TO WARRANT AN ADVISORY...BUT WILL CONTINUE TO
MONITOR TRENDS. IF FOG IS WELL ESTABLISHED BY MIDNIGHT...THE
LIKELIHOOD OF DENSE FOG DURING THE MORNING COMMUTE WILL INCREASE
CONSIDERABLY.
25
&&
.PREV DISCUSSION... /ISSUED 342 PM CDT SUN MAR 22 2015/
WATER VAPOR SATELLITE IMAGERY SHOWED A SHORTWAVE TROUGH OVER THE
ARKLATEX AREA...MOVING EAST-NORTHEAST AWAY FROM NORTH TEXAS.
BEHIND THIS TROUGH...LARGE SCALE FORCING FOR SUBSIDENCE WAS
BEGINNING TO CLEAR OUT THICK CLOUD COVER OVER NORTH TEXAS THIS
AFTERNOON. AT THE SURFACE...A RIDGE OF HIGH PRESSURE WAS IN PLACE
OVER NORTH TEXAS...RESULTING IN LIGHT NORTHERLY WINDS FOR MOST
LOCATIONS.
FOR TONIGHT...SKIES ARE EXPECTED TO BECOME MOSTLY CLEAR AS LARGE
SCALE FORCING FOR SUBSIDENCE CONTINUES OVER THE REGION. HIGH
PRESSURE AT THE SURFACE IS EXPECTED TO MOVE SLIGHTLY EAST
TONIGHT...RESULTING IN VERY LIGHT EAST TO SOUTHEASTERLY WINDS
ACROSS THE CWA. IF SUBSIDENCE IS ABLE TO CLEAR OUT SKIES
TONIGHT...AN IDEAL ENVIRONMENT FOR RADIATIONAL COOLING IS
EXPECTED TO BRING TEMPERATURES DOWN INTO THE UPPER 40S TO LOWER
50S BY MONDAY MORNING. WITH DEW POINT VALUES THIS AFTERNOON
OBSERVED IN THE LOWER TO MID 50S ACROSS THE AREA...TEMPERATURES
ARE EXPECTED TO BECOME COLD ENOUGH...AND WINDS ARE EXPECTED TO
REMAIN LIGHT ENOUGH...FOR AREAS OF FOG TO DEVELOP BEFORE SUNRISE
TOMORROW MORNING. THE THICKNESS OF THE FOG WILL DEPEND ON JUST HOW
MUCH CLOUD COVER CAN CLEAR OUT TONIGHT.
IF SKIES BECOME CLEAR...CHANCES ARE HIGH THAT DENSE FOG WILL
DEVELOP ACROSS THE REGION BY EARLY TOMORROW MORNING...AND A DENSE
FOG WILL NEED TO BE ISSUED AS A RESULT. HELD OFF ON ISSUING A
DENSE FOG ADVISORY FOR NOW AS WE`D LIKE TO SEE THE SUBSIDENCE
ACTUALLY CLEAR OUT THE CLOUDS BEFORE BUYING IN ON AREAS OF DENSE
FOG. SOME FOG IS LIKELY TO DEVELOP REGARDLESS OF HOW MUCH CLOUD
COVER REMAINS IN PLACE...HOWEVER GETTING WIDESPREAD VISIBILITIES
DOWN TO ONE QUARTER MILE OR BELOW WILL BE DIFFICULT WITHOUT CLEAR
SKIES TONIGHT.
UPPER LEVEL RIDGING IS EXPECTED TO BUILD OVER THE REGION ON
MONDAY...WHICH WILL SUPPORT MOSTLY SUNNY SKIES AND TEMPERATURES
CLIMBING 10 TO 15 DEGREES WARMER THAN TODAY. WINDS ARE EXPECTED TO
VEER AROUND TO THE SOUTH WHICH WILL HELP KEEP LOW- LEVEL MOISTURE
IN PLACE...AND SEND SOME ADDITIONAL GULF MOISTURE INTO THE REGION
FOR TUESDAY AND WEDNESDAY.
ON TUESDAY...A SHORTWAVE TROUGH CURRENTLY LOCATED APPROXIMATELY
400 MILES WEST OF THE NORTHERN CALIFORNIA COAST IS EXPECTED TO
MOVE EAST OVER THE CENTRAL PLAINS...SENDING A PACIFIC-TYPE COLD
FRONT SOUTHEAST ACROSS THE SOUTHERN HIGH PLAINS TOWARDS NORTH
TEXAS. THIS BOUNDARY IS EXPECTED TO STALL OUT IN THE NORTHWEST
PORTIONS OF THE CWA TUESDAY AFTERNOON. DOWNSLOPE FLOW AND DRIER
AIR BEHIND THIS BOUNDARY WILL RESULT IN TEMPERATURES CLIMBING INTO
THE UPPER 80S OVER THE WESTERN QUARTER OF THE CWA. TEMPERATURES
ARE EXPECTED TO CLIMB TO RIGHT AROUND 80 DEGREES TO THE EAST
WHERE LOW-LEVEL MOISTURE AND SOME AFTERNOON CUMULUS CLOUDS WILL
LIKELY REMAIN IN PLACE.
THERE WILL BE SOME LIFT ALONG THE STALLED OUT BOUNDARY ON
TUESDAY...HOWEVER FORECAST SOUNDINGS INDICATE THAT A SUBSTANTIAL
CAP WILL BE IN PLACE. THIS CAP APPEARS TO BE STOUT ENOUGH TO
PREVENT THUNDERSTORMS FROM DEVELOPING ACROSS NORTH TEXAS TUESDAY
AFTERNOON...HOWEVER MODEL OUTPUT FROM THE ECMWF/GFS/NAM HINT AT A
SUFFICIENT AMOUNT OF LIFT TO TRIGGER THE SHALLOW CONVECTION
SCHEMES OF THESE MODELS. THIS CAN BE VISUALIZED AS A SUDDEN
INCREASE IN RELATIVE HUMIDITY IN THE MIDDLE TROPOSPHERE AROUND 00Z
WEDNESDAY (WHICH IS TUESDAY 7 PM). BECAUSE THE FORECAST SOUNDINGS
ARE ADVERTISING A STOUT CAP...AND MODELS ARE ADVERTISING
RELATIVELY WEAK LIFT ALONG THE BOUNDARY...DECIDED TO ONLY MENTION
A 10 PERCENT CHANCE OF STORMS NEAR THE STALLED OUT BOUNDARY
TUESDAY AFTERNOON AND EVENING. IF A STORM WAS ABLE TO
DEVELOP...THERE IS A CHANCE IT WOULD BE STRONG OR SEVERE WITH CAPE
VALUES FORECAST TO BE IN THE NEIGHBORHOOD OF 1500-2000 J/KG AND
DEEP LAYER BULK SHEAR OF AROUND 35 KTS. CHANCES ARE WE WILL NOT
SEE STORMS THIS FAR SOUTH HOWEVER. EXPECT MOST THUNDERSTORM
ACTIVITY WILL REMAIN IN OKLAHOMA...CLOSER TO THE SHORTWAVE TROUGH.
ANOTHER STRONG SHORTWAVE TROUGH IS EXPECTED TO MOVE OVER THE
PLAINS WEDNESDAY AFTERNOON AND EVENING. THIS TROUGH IS EXPECTED TO
SPREAD STRONG FORCING FOR ASCENT AS FAR SOUTH AS THE RED
RIVER...SO OUR CHANCES FOR STORMS ALONG THE PACIFIC-FRONT OR
DRYLINE ARE BETTER AS A RESULT. FORECAST SOUNDINGS CONSISTENTLY
ADVERTISE A STRONG CAP IN PLACE OVER THE REGION ON WEDNESDAY...SO
EXPECT THAT IF ANY STORMS DEVELOP...THEY WILL REMAIN CLOSELY TIED
TO THE FRONT. WITH STRONGER LIFT EXPECTED...WENT AHEAD WITH A 20
TO 30 PERCENT CHANCE OF STORMS WEDNESDAY AFTERNOON...GENERALLY
WEST AND NORTHWEST OF THE DFW METROPLEX. THE SHORTWAVE TROUGH
WILL EVENTUALLY SEND THE STALLED OUT PACIFIC-TYPE COLD FRONT
SOUTHEAST ACROSS NORTH TEXAS FROM WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. ONCE THE FRONT STARTS MOVING...THUNDERSTORMS ARE
EXPECTED TO GROW UPSCALE ALONG THE FRONT INTO A SQUALL LINE AND
ACCOMPANY THE FRONT SOUTHEAST ACROSS THE CWA.
IF STORMS ARE ABLE TO DEVELOP WEDNESDAY AFTERNOON BEFORE THE FRONT
STARTS TO MOVE...STORMS WILL HAVE A GOOD CHANCE AT BECOMING
ORGANIZED QUICKLY INTO STRONG TO SEVERE STORMS. CAPE VALUES ARE
EXPECTED TO CLIMB TO 2000 TO 2500 J/KG WHILE DEEP LAYER BULK SHEAR
VALUES CLIMB TO 45 TO 50 KTS. THE COMBINATION OF THESE
PARAMETERS...THE FORCING FOR ASCENT LIMITED TO A RELATIVELY SMALL
AREA NEAR THE STALLED OUT BOUNDARY...AND THE CAP IN PLACE WOULD
INITIALLY FAVOR A DISCRETE STORM MODE WEDNESDAY AFTERNOON.
IF STORMS ARE ABLE TO DEVELOP...THIS WOULD PROBABLY SUPPORT A
RISK OF DISCRETE SUPERCELLS UNTIL THE FRONT STARTS TO MOVE
WEDNESDAY EVENING. ONCE THE FRONT MOVES...STRONGER LIFT SHOULD
WEAKEN THE CAP OVER A LARGER AREA RESULTING IN THE UPSCALE GROWTH
OF DISCRETE STORMS INTO A SQUALL LINE. HAIL AND DAMAGING WINDS
LOOK TO BE THE PRIMARY THREATS ASSOCIATED WITH ANY SEVERE STORMS
ON WEDNESDAY...TRANSITIONING OVER TO PRIMARILY A DAMAGING WIND
THREAT WEDNESDAY EVENING AND OVERNIGHT.
IT IS TOO EARLY TO REALLY ASSESS THE TORNADO THREAT...HOWEVER A
QUICK LOOK AT PARAMETERS SHOWS LOW-LEVEL SHEAR VALUES ARE
SOMEWHAT MEAGER...SO CURRENT THINKING IS THAT THE PRIMARY SEVERE
WEATHER THREATS ARE DAMAGING WINDS AND HAIL. THIS MAY CHANGE AS WE
GET CLOSER TO WEDNESDAY OF COURSE AND CAN ASSESS SMALLER SCALE
FEATURES. WHILE FLOODING DOES NOT APPEAR TO BE A WIDESPREAD
CONCERN WITH STORMS REMAINING CLOSELY TIED TO A MOVING
FRONT...LOCALLY HEAVY RAINFALL/FLOODING IS CERTAINLY A POSSIBILITY
ASSUMING A SQUALL LINE DEVELOPS AND MOVES SOUTHEAST ACROSS MUCH OF
THE CWA.
BEHIND THE FRONT...DRIER AIR IS EXPECTED TO BUILD INTO THE
REGION...WHICH SHOULD RESULT IN A DRY FORECAST FOR THE REMAINDER
OF THE WEEK. TEMPERATURES ARE EXPECTED TO BE BELOW NORMAL AT THE
END OF THE WEEK BEHIND THE FRONT WITH A COOLER AND DRIER AIR MASS
IN PLACE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 49 76 59 81 60 / 0 0 5 10 10
WACO, TX 48 77 57 80 59 / 0 0 5 5 10
PARIS, TX 46 74 52 77 56 / 0 0 5 5 20
DENTON, TX 48 76 58 82 57 / 0 0 5 10 10
MCKINNEY, TX 47 75 56 79 58 / 0 0 5 10 20
DALLAS, TX 51 76 59 80 61 / 0 0 5 10 10
TERRELL, TX 47 75 56 78 59 / 0 0 5 5 10
CORSICANA, TX 49 76 56 79 60 / 0 0 5 5 10
TEMPLE, TX 50 77 56 79 58 / 0 0 5 5 5
MINERAL WELLS, TX 49 79 59 85 56 / 0 0 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
58/25
Area Forecast Discussion
National Weather Service Spokane WA
221 AM PDT MON MAR 23 2015
.SYNOPSIS...
Showery and seasonably cool weather will remain in place through
midweek. By the end of the week strong ridging will build over the
region bringing a gradual warming and drying trend.
&&
.DISCUSSION...
Today through Tuesday...A cool upper level trough will descend
into the region today from the Gulf of Alaska bearing multiple
waves of moisture over the next 36 hours leading to an
unsettled...cool...showery and raw period through Wednesday.
The first wave of moisture will sweep through this morning as a
cold front with dense showers along and immediately behind the
front...with upslope showers continuing to drive into the Idaho
Panhandle through today while a partial rain shadow allows shower
activity to decrease to isolated by this afternoon in the deep
basin. Snow levels with this initial wave will remain in the 4000
to 5000 foot range. The post front air mass will also promote
breezy conditions across the exposed terrain of the eastern basin.
Temperatures will crest out right around normal for this time of
year.
Late this afternoon and evening the wave of enhancement visible on
satellite moving into the Oregon Coast will pass through to keep
scattered to numerous showers going through the evening especially
over the Idaho Panhandle.
Through today and this evening the cool air aloft in the trough
will bring some moderate instability leading to a chance of a few
minor thunderstorms tracking through the region...mainly north
and east of the Spokane area.
Overnight tonight and into Tuesday a third system is sensed by
all the latest model runs to move along the Washington/Oregon
border as a weak surface low pressure. This track will place the
forecast area south of Interstate 90 under the mid level TROWAL
region and promote another round of precipitation...however the
time of day will mandate mention of snow or snow/rain mix down to
as low as 2000 feet especially over the Palouse and points
southward. elevations above 3000 feet may receive a couple inches
of snow including the Camas Prairie and the I-90 corridor leading
up to Lookout Pass...although road surface temperatures may be
high enough to minimize accumulation on the pavement surfaces.
below 3000 feet little or no accumulation is probable. During the
day Tuesday the unsettled and showery conditions will persist
with the densest concentration of valley rain/mountain snow
showers over the panhandle and the least areal extent...isolated
or null...over the deep basin/Cascades lee zones. /Fugazzi
Tuesday night through Thursday: The trof responsible for our unsettled
weather pattern at the start of the week will finally begin to
shift east and a ridge of high pressure will nudge inland.
Lingering showers across the Idaho Panhandle Tuesday evening will
decrease overnight and the region will be in a drier northwest
flow regime bringing a brief break in the wet weather overnight.
The ridge will have a plume of subtropical moisture draped across it as
it comes inland Wednesday before amplifying Thursday. This rich
axis of moisture accompanying the building ridge will equate to
mostly cloudy skies and chance for periods of light precipitation.
Just about every location will carry a chance for precipitation
but should see less than 0.05" of liquid between Wednesday and
Thursday morning. The exception could be in the North Cascades
which will have the potential for upwards of a tenth to quarter
inch of liquid.
Thursday night through Monday: The ridge will be the dominate feature
Thursday night and Friday steering any storm systems well around
the area and promoting abundance of sunshine and above normal
warmth. By Saturday, models project a shortwave trof to track off
the Pacific and give the ridge its first blow. This wave looks to
dent the ridge and usher a weak cool front through but for the
most part, split with one area of low pressure pinching off over
California and a second, weaker wave crossing southern BC. This
will keep mention of a few light showers across the mountains near
the International Border. On another note, GFS/ECMWF are also
indicating light QPF in the vicinity of the Blue Mtns and lower ID
Panhandle associated with afternoon thunderstorms. The instability
is tied to an axis of 50F dewpoints modeled on each of these
models. Models have a tendency to moisten lower-levels too
aggressively, especially in the extended so at this point, it is
worth keeping an eye on, but will leave out thunder wording.
As this first blow passes through, the ridge rebuilds but the west
is now within a split flow regime as low pressure resides in
CA/NV area and the ridge amplifies over BC. Medium range models
are in decent agreement with the field of motion but have some
features displaced. Needless to say, it looks as if the pattern
will deflect the next wave of moisture to our north Sunday but a
stronger and wetter system looks to finally break down the ridge
early next week bringing the next round of showers, breezy winds,
and perhaps thunder. So despite the absence of old man winter in
the region, Spring looks like it`s right on track. /sb
&&
.AVIATION...
06Z TAFS: A mesoscale low pressure system will bring rain to most
aviation areas tonight into tomorrow morning. A second weather
disturbance working with an unstable airmass will bring mostly
rain showers with some thunderstorms Monday afternoon and early
evening. Expectation is rain will be the major precipitation type
with perhaps some graupel or small soft hail associated with some
of the thunderstorms and perhaps MVFR visibility and ceilings
associated with the precipitation. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 51 34 49 31 53 39 / 60 40 40 20 20 20
Coeur d`Alene 50 33 48 30 51 35 / 80 50 40 20 30 30
Pullman 50 35 47 33 53 39 / 80 60 70 30 20 30
Lewiston 53 37 52 35 56 40 / 70 50 60 20 20 20
Colville 54 33 54 30 54 32 / 60 50 50 20 20 20
Sandpoint 49 32 49 31 50 33 / 90 60 50 30 30 30
Kellogg 46 33 45 32 48 35 / 100 70 70 40 30 40
Moses Lake 58 36 58 33 60 40 / 20 20 30 10 10 20
Wenatchee 58 40 57 38 60 42 / 20 40 20 10 20 20
Omak 57 34 58 31 57 36 / 20 20 20 10 20 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
221 AM PDT MON MAR 23 2015
.SYNOPSIS...
Showery and seasonably cool weather will remain in place through
midweek. By the end of the week strong ridging will build over the
region bringing a gradual warming and drying trend.
&&
.DISCUSSION...
Today through Tuesday...A cool upper level trough will descend
into the region today from the Gulf of Alaska bearing multiple
waves of moisture over the next 36 hours leading to an
unsettled...cool...showery and raw period through Wednesday.
The first wave of moisture will sweep through this morning as a
cold front with dense showers along and immediately behind the
front...with upslope showers continuing to drive into the Idaho
Panhandle through today while a partial rain shadow allows shower
activity to decrease to isolated by this afternoon in the deep
basin. Snow levels with this initial wave will remain in the 4000
to 5000 foot range. The post front air mass will also promote
breezy conditions across the exposed terrain of the eastern basin.
Temperatures will crest out right around normal for this time of
year.
Late this afternoon and evening the wave of enhancement visible on
satellite moving into the Oregon Coast will pass through to keep
scattered to numerous showers going through the evening especially
over the Idaho Panhandle.
Through today and this evening the cool air aloft in the trough
will bring some moderate instability leading to a chance of a few
minor thunderstorms tracking through the region...mainly north
and east of the Spokane area.
Overnight tonight and into Tuesday a third system is sensed by
all the latest model runs to move along the Washington/Oregon
border as a weak surface low pressure. This track will place the
forecast area south of Interstate 90 under the mid level TROWAL
region and promote another round of precipitation...however the
time of day will mandate mention of snow or snow/rain mix down to
as low as 2000 feet especially over the Palouse and points
southward. elevations above 3000 feet may receive a couple inches
of snow including the Camas Prairie and the I-90 corridor leading
up to Lookout Pass...although road surface temperatures may be
high enough to minimize accumulation on the pavement surfaces.
below 3000 feet little or no accumulation is probable. During the
day Tuesday the unsettled and showery conditions will persist
with the densest concentration of valley rain/mountain snow
showers over the panhandle and the least areal extent...isolated
or null...over the deep basin/Cascades lee zones. /Fugazzi
Tuesday night through Thursday: The trof responsible for our unsettled
weather pattern at the start of the week will finally begin to
shift east and a ridge of high pressure will nudge inland.
Lingering showers across the Idaho Panhandle Tuesday evening will
decrease overnight and the region will be in a drier northwest
flow regime bringing a brief break in the wet weather overnight.
The ridge will have a plume of subtropical moisture draped across it as
it comes inland Wednesday before amplifying Thursday. This rich
axis of moisture accompanying the building ridge will equate to
mostly cloudy skies and chance for periods of light precipitation.
Just about every location will carry a chance for precipitation
but should see less than 0.05" of liquid between Wednesday and
Thursday morning. The exception could be in the North Cascades
which will have the potential for upwards of a tenth to quarter
inch of liquid.
Thursday night through Monday: The ridge will be the dominate feature
Thursday night and Friday steering any storm systems well around
the area and promoting abundance of sunshine and above normal
warmth. By Saturday, models project a shortwave trof to track off
the Pacific and give the ridge its first blow. This wave looks to
dent the ridge and usher a weak cool front through but for the
most part, split with one area of low pressure pinching off over
California and a second, weaker wave crossing southern BC. This
will keep mention of a few light showers across the mountains near
the International Border. On another note, GFS/ECMWF are also
indicating light QPF in the vicinity of the Blue Mtns and lower ID
Panhandle associated with afternoon thunderstorms. The instability
is tied to an axis of 50F dewpoints modeled on each of these
models. Models have a tendency to moisten lower-levels too
aggressively, especially in the extended so at this point, it is
worth keeping an eye on, but will leave out thunder wording.
As this first blow passes through, the ridge rebuilds but the west
is now within a split flow regime as low pressure resides in
CA/NV area and the ridge amplifies over BC. Medium range models
are in decent agreement with the field of motion but have some
features displaced. Needless to say, it looks as if the pattern
will deflect the next wave of moisture to our north Sunday but a
stronger and wetter system looks to finally break down the ridge
early next week bringing the next round of showers, breezy winds,
and perhaps thunder. So despite the absence of old man winter in
the region, Spring looks like it`s right on track. /sb
&&
.AVIATION...
06Z TAFS: A mesoscale low pressure system will bring rain to most
aviation areas tonight into tomorrow morning. A second weather
disturbance working with an unstable airmass will bring mostly
rain showers with some thunderstorms Monday afternoon and early
evening. Expectation is rain will be the major precipitation type
with perhaps some graupel or small soft hail associated with some
of the thunderstorms and perhaps MVFR visibility and ceilings
associated with the precipitation. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 51 34 49 31 53 39 / 60 40 40 20 20 20
Coeur d`Alene 50 33 48 30 51 35 / 80 50 40 20 30 30
Pullman 50 35 47 33 53 39 / 80 60 70 30 20 30
Lewiston 53 37 52 35 56 40 / 70 50 60 20 20 20
Colville 54 33 54 30 54 32 / 60 50 50 20 20 20
Sandpoint 49 32 49 31 50 33 / 90 60 50 30 30 30
Kellogg 46 33 45 32 48 35 / 100 70 70 40 30 40
Moses Lake 58 36 58 33 60 40 / 20 20 30 10 10 20
Wenatchee 58 40 57 38 60 42 / 20 40 20 10 20 20
Omak 57 34 58 31 57 36 / 20 20 20 10 20 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
221 AM PDT MON MAR 23 2015
.SYNOPSIS...
Showery and seasonably cool weather will remain in place through
midweek. By the end of the week strong ridging will build over the
region bringing a gradual warming and drying trend.
&&
.DISCUSSION...
Today through Tuesday...A cool upper level trough will descend
into the region today from the Gulf of Alaska bearing multiple
waves of moisture over the next 36 hours leading to an
unsettled...cool...showery and raw period through Wednesday.
The first wave of moisture will sweep through this morning as a
cold front with dense showers along and immediately behind the
front...with upslope showers continuing to drive into the Idaho
Panhandle through today while a partial rain shadow allows shower
activity to decrease to isolated by this afternoon in the deep
basin. Snow levels with this initial wave will remain in the 4000
to 5000 foot range. The post front air mass will also promote
breezy conditions across the exposed terrain of the eastern basin.
Temperatures will crest out right around normal for this time of
year.
Late this afternoon and evening the wave of enhancement visible on
satellite moving into the Oregon Coast will pass through to keep
scattered to numerous showers going through the evening especially
over the Idaho Panhandle.
Through today and this evening the cool air aloft in the trough
will bring some moderate instability leading to a chance of a few
minor thunderstorms tracking through the region...mainly north
and east of the Spokane area.
Overnight tonight and into Tuesday a third system is sensed by
all the latest model runs to move along the Washington/Oregon
border as a weak surface low pressure. This track will place the
forecast area south of Interstate 90 under the mid level TROWAL
region and promote another round of precipitation...however the
time of day will mandate mention of snow or snow/rain mix down to
as low as 2000 feet especially over the Palouse and points
southward. elevations above 3000 feet may receive a couple inches
of snow including the Camas Prairie and the I-90 corridor leading
up to Lookout Pass...although road surface temperatures may be
high enough to minimize accumulation on the pavement surfaces.
below 3000 feet little or no accumulation is probable. During the
day Tuesday the unsettled and showery conditions will persist
with the densest concentration of valley rain/mountain snow
showers over the panhandle and the least areal extent...isolated
or null...over the deep basin/Cascades lee zones. /Fugazzi
Tuesday night through Thursday: The trof responsible for our unsettled
weather pattern at the start of the week will finally begin to
shift east and a ridge of high pressure will nudge inland.
Lingering showers across the Idaho Panhandle Tuesday evening will
decrease overnight and the region will be in a drier northwest
flow regime bringing a brief break in the wet weather overnight.
The ridge will have a plume of subtropical moisture draped across it as
it comes inland Wednesday before amplifying Thursday. This rich
axis of moisture accompanying the building ridge will equate to
mostly cloudy skies and chance for periods of light precipitation.
Just about every location will carry a chance for precipitation
but should see less than 0.05" of liquid between Wednesday and
Thursday morning. The exception could be in the North Cascades
which will have the potential for upwards of a tenth to quarter
inch of liquid.
Thursday night through Monday: The ridge will be the dominate feature
Thursday night and Friday steering any storm systems well around
the area and promoting abundance of sunshine and above normal
warmth. By Saturday, models project a shortwave trof to track off
the Pacific and give the ridge its first blow. This wave looks to
dent the ridge and usher a weak cool front through but for the
most part, split with one area of low pressure pinching off over
California and a second, weaker wave crossing southern BC. This
will keep mention of a few light showers across the mountains near
the International Border. On another note, GFS/ECMWF are also
indicating light QPF in the vicinity of the Blue Mtns and lower ID
Panhandle associated with afternoon thunderstorms. The instability
is tied to an axis of 50F dewpoints modeled on each of these
models. Models have a tendency to moisten lower-levels too
aggressively, especially in the extended so at this point, it is
worth keeping an eye on, but will leave out thunder wording.
As this first blow passes through, the ridge rebuilds but the west
is now within a split flow regime as low pressure resides in
CA/NV area and the ridge amplifies over BC. Medium range models
are in decent agreement with the field of motion but have some
features displaced. Needless to say, it looks as if the pattern
will deflect the next wave of moisture to our north Sunday but a
stronger and wetter system looks to finally break down the ridge
early next week bringing the next round of showers, breezy winds,
and perhaps thunder. So despite the absence of old man winter in
the region, Spring looks like it`s right on track. /sb
&&
.AVIATION...
06Z TAFS: A mesoscale low pressure system will bring rain to most
aviation areas tonight into tomorrow morning. A second weather
disturbance working with an unstable airmass will bring mostly
rain showers with some thunderstorms Monday afternoon and early
evening. Expectation is rain will be the major precipitation type
with perhaps some graupel or small soft hail associated with some
of the thunderstorms and perhaps MVFR visibility and ceilings
associated with the precipitation. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 51 34 49 31 53 39 / 60 40 40 20 20 20
Coeur d`Alene 50 33 48 30 51 35 / 80 50 40 20 30 30
Pullman 50 35 47 33 53 39 / 80 60 70 30 20 30
Lewiston 53 37 52 35 56 40 / 70 50 60 20 20 20
Colville 54 33 54 30 54 32 / 60 50 50 20 20 20
Sandpoint 49 32 49 31 50 33 / 90 60 50 30 30 30
Kellogg 46 33 45 32 48 35 / 100 70 70 40 30 40
Moses Lake 58 36 58 33 60 40 / 20 20 30 10 10 20
Wenatchee 58 40 57 38 60 42 / 20 40 20 10 20 20
Omak 57 34 58 31 57 36 / 20 20 20 10 20 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
221 AM PDT MON MAR 23 2015
.SYNOPSIS...
Showery and seasonably cool weather will remain in place through
midweek. By the end of the week strong ridging will build over the
region bringing a gradual warming and drying trend.
&&
.DISCUSSION...
Today through Tuesday...A cool upper level trough will descend
into the region today from the Gulf of Alaska bearing multiple
waves of moisture over the next 36 hours leading to an
unsettled...cool...showery and raw period through Wednesday.
The first wave of moisture will sweep through this morning as a
cold front with dense showers along and immediately behind the
front...with upslope showers continuing to drive into the Idaho
Panhandle through today while a partial rain shadow allows shower
activity to decrease to isolated by this afternoon in the deep
basin. Snow levels with this initial wave will remain in the 4000
to 5000 foot range. The post front air mass will also promote
breezy conditions across the exposed terrain of the eastern basin.
Temperatures will crest out right around normal for this time of
year.
Late this afternoon and evening the wave of enhancement visible on
satellite moving into the Oregon Coast will pass through to keep
scattered to numerous showers going through the evening especially
over the Idaho Panhandle.
Through today and this evening the cool air aloft in the trough
will bring some moderate instability leading to a chance of a few
minor thunderstorms tracking through the region...mainly north
and east of the Spokane area.
Overnight tonight and into Tuesday a third system is sensed by
all the latest model runs to move along the Washington/Oregon
border as a weak surface low pressure. This track will place the
forecast area south of Interstate 90 under the mid level TROWAL
region and promote another round of precipitation...however the
time of day will mandate mention of snow or snow/rain mix down to
as low as 2000 feet especially over the Palouse and points
southward. elevations above 3000 feet may receive a couple inches
of snow including the Camas Prairie and the I-90 corridor leading
up to Lookout Pass...although road surface temperatures may be
high enough to minimize accumulation on the pavement surfaces.
below 3000 feet little or no accumulation is probable. During the
day Tuesday the unsettled and showery conditions will persist
with the densest concentration of valley rain/mountain snow
showers over the panhandle and the least areal extent...isolated
or null...over the deep basin/Cascades lee zones. /Fugazzi
Tuesday night through Thursday: The trof responsible for our unsettled
weather pattern at the start of the week will finally begin to
shift east and a ridge of high pressure will nudge inland.
Lingering showers across the Idaho Panhandle Tuesday evening will
decrease overnight and the region will be in a drier northwest
flow regime bringing a brief break in the wet weather overnight.
The ridge will have a plume of subtropical moisture draped across it as
it comes inland Wednesday before amplifying Thursday. This rich
axis of moisture accompanying the building ridge will equate to
mostly cloudy skies and chance for periods of light precipitation.
Just about every location will carry a chance for precipitation
but should see less than 0.05" of liquid between Wednesday and
Thursday morning. The exception could be in the North Cascades
which will have the potential for upwards of a tenth to quarter
inch of liquid.
Thursday night through Monday: The ridge will be the dominate feature
Thursday night and Friday steering any storm systems well around
the area and promoting abundance of sunshine and above normal
warmth. By Saturday, models project a shortwave trof to track off
the Pacific and give the ridge its first blow. This wave looks to
dent the ridge and usher a weak cool front through but for the
most part, split with one area of low pressure pinching off over
California and a second, weaker wave crossing southern BC. This
will keep mention of a few light showers across the mountains near
the International Border. On another note, GFS/ECMWF are also
indicating light QPF in the vicinity of the Blue Mtns and lower ID
Panhandle associated with afternoon thunderstorms. The instability
is tied to an axis of 50F dewpoints modeled on each of these
models. Models have a tendency to moisten lower-levels too
aggressively, especially in the extended so at this point, it is
worth keeping an eye on, but will leave out thunder wording.
As this first blow passes through, the ridge rebuilds but the west
is now within a split flow regime as low pressure resides in
CA/NV area and the ridge amplifies over BC. Medium range models
are in decent agreement with the field of motion but have some
features displaced. Needless to say, it looks as if the pattern
will deflect the next wave of moisture to our north Sunday but a
stronger and wetter system looks to finally break down the ridge
early next week bringing the next round of showers, breezy winds,
and perhaps thunder. So despite the absence of old man winter in
the region, Spring looks like it`s right on track. /sb
&&
.AVIATION...
06Z TAFS: A mesoscale low pressure system will bring rain to most
aviation areas tonight into tomorrow morning. A second weather
disturbance working with an unstable airmass will bring mostly
rain showers with some thunderstorms Monday afternoon and early
evening. Expectation is rain will be the major precipitation type
with perhaps some graupel or small soft hail associated with some
of the thunderstorms and perhaps MVFR visibility and ceilings
associated with the precipitation. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 51 34 49 31 53 39 / 60 40 40 20 20 20
Coeur d`Alene 50 33 48 30 51 35 / 80 50 40 20 30 30
Pullman 50 35 47 33 53 39 / 80 60 70 30 20 30
Lewiston 53 37 52 35 56 40 / 70 50 60 20 20 20
Colville 54 33 54 30 54 32 / 60 50 50 20 20 20
Sandpoint 49 32 49 31 50 33 / 90 60 50 30 30 30
Kellogg 46 33 45 32 48 35 / 100 70 70 40 30 40
Moses Lake 58 36 58 33 60 40 / 20 20 30 10 10 20
Wenatchee 58 40 57 38 60 42 / 20 40 20 10 20 20
Omak 57 34 58 31 57 36 / 20 20 20 10 20 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
221 AM PDT MON MAR 23 2015
.SYNOPSIS...
Showery and seasonably cool weather will remain in place through
midweek. By the end of the week strong ridging will build over the
region bringing a gradual warming and drying trend.
&&
.DISCUSSION...
Today through Tuesday...A cool upper level trough will descend
into the region today from the Gulf of Alaska bearing multiple
waves of moisture over the next 36 hours leading to an
unsettled...cool...showery and raw period through Wednesday.
The first wave of moisture will sweep through this morning as a
cold front with dense showers along and immediately behind the
front...with upslope showers continuing to drive into the Idaho
Panhandle through today while a partial rain shadow allows shower
activity to decrease to isolated by this afternoon in the deep
basin. Snow levels with this initial wave will remain in the 4000
to 5000 foot range. The post front air mass will also promote
breezy conditions across the exposed terrain of the eastern basin.
Temperatures will crest out right around normal for this time of
year.
Late this afternoon and evening the wave of enhancement visible on
satellite moving into the Oregon Coast will pass through to keep
scattered to numerous showers going through the evening especially
over the Idaho Panhandle.
Through today and this evening the cool air aloft in the trough
will bring some moderate instability leading to a chance of a few
minor thunderstorms tracking through the region...mainly north
and east of the Spokane area.
Overnight tonight and into Tuesday a third system is sensed by
all the latest model runs to move along the Washington/Oregon
border as a weak surface low pressure. This track will place the
forecast area south of Interstate 90 under the mid level TROWAL
region and promote another round of precipitation...however the
time of day will mandate mention of snow or snow/rain mix down to
as low as 2000 feet especially over the Palouse and points
southward. elevations above 3000 feet may receive a couple inches
of snow including the Camas Prairie and the I-90 corridor leading
up to Lookout Pass...although road surface temperatures may be
high enough to minimize accumulation on the pavement surfaces.
below 3000 feet little or no accumulation is probable. During the
day Tuesday the unsettled and showery conditions will persist
with the densest concentration of valley rain/mountain snow
showers over the panhandle and the least areal extent...isolated
or null...over the deep basin/Cascades lee zones. /Fugazzi
Tuesday night through Thursday: The trof responsible for our unsettled
weather pattern at the start of the week will finally begin to
shift east and a ridge of high pressure will nudge inland.
Lingering showers across the Idaho Panhandle Tuesday evening will
decrease overnight and the region will be in a drier northwest
flow regime bringing a brief break in the wet weather overnight.
The ridge will have a plume of subtropical moisture draped across it as
it comes inland Wednesday before amplifying Thursday. This rich
axis of moisture accompanying the building ridge will equate to
mostly cloudy skies and chance for periods of light precipitation.
Just about every location will carry a chance for precipitation
but should see less than 0.05" of liquid between Wednesday and
Thursday morning. The exception could be in the North Cascades
which will have the potential for upwards of a tenth to quarter
inch of liquid.
Thursday night through Monday: The ridge will be the dominate feature
Thursday night and Friday steering any storm systems well around
the area and promoting abundance of sunshine and above normal
warmth. By Saturday, models project a shortwave trof to track off
the Pacific and give the ridge its first blow. This wave looks to
dent the ridge and usher a weak cool front through but for the
most part, split with one area of low pressure pinching off over
California and a second, weaker wave crossing southern BC. This
will keep mention of a few light showers across the mountains near
the International Border. On another note, GFS/ECMWF are also
indicating light QPF in the vicinity of the Blue Mtns and lower ID
Panhandle associated with afternoon thunderstorms. The instability
is tied to an axis of 50F dewpoints modeled on each of these
models. Models have a tendency to moisten lower-levels too
aggressively, especially in the extended so at this point, it is
worth keeping an eye on, but will leave out thunder wording.
As this first blow passes through, the ridge rebuilds but the west
is now within a split flow regime as low pressure resides in
CA/NV area and the ridge amplifies over BC. Medium range models
are in decent agreement with the field of motion but have some
features displaced. Needless to say, it looks as if the pattern
will deflect the next wave of moisture to our north Sunday but a
stronger and wetter system looks to finally break down the ridge
early next week bringing the next round of showers, breezy winds,
and perhaps thunder. So despite the absence of old man winter in
the region, Spring looks like it`s right on track. /sb
&&
.AVIATION...
06Z TAFS: A mesoscale low pressure system will bring rain to most
aviation areas tonight into tomorrow morning. A second weather
disturbance working with an unstable airmass will bring mostly
rain showers with some thunderstorms Monday afternoon and early
evening. Expectation is rain will be the major precipitation type
with perhaps some graupel or small soft hail associated with some
of the thunderstorms and perhaps MVFR visibility and ceilings
associated with the precipitation. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 51 34 49 31 53 39 / 60 40 40 20 20 20
Coeur d`Alene 50 33 48 30 51 35 / 80 50 40 20 30 30
Pullman 50 35 47 33 53 39 / 80 60 70 30 20 30
Lewiston 53 37 52 35 56 40 / 70 50 60 20 20 20
Colville 54 33 54 30 54 32 / 60 50 50 20 20 20
Sandpoint 49 32 49 31 50 33 / 90 60 50 30 30 30
Kellogg 46 33 45 32 48 35 / 100 70 70 40 30 40
Moses Lake 58 36 58 33 60 40 / 20 20 30 10 10 20
Wenatchee 58 40 57 38 60 42 / 20 40 20 10 20 20
Omak 57 34 58 31 57 36 / 20 20 20 10 20 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
949 PM PDT SUN MAR 22 2015
.SYNOPSIS...
Wet and unsettled weather will remain in place through midweek.
By the end of the week strong ridging will build over the region
bringing a gradual warming and drying trend.
&&
.DISCUSSION...
Updated the zone forecasts to rework the wording and remove part
of the early evening break in the precipitation. Radar along with
the HRRR progs suggest the precipitation approaching and moving
into the area from the southwest will increase and intensify
tonight as per the earlier forecast trended toward. Additionally
have made minor adjustments to cool a forecast low or two in the
area a degree or so. Negatively tilted trof passage with cold pool
aloft producing instability to utilize is still the scenario
show by the short term models for Monday afternoon and evening so
the mention of showers and thunderstorms in that interval remains
the same with little to no modification. /Pelatti
&&
.AVIATION...
06Z TAFS: A mesoscale low pressure system will bring rain to most
aviation areas tonight into tomorrow morning. A second weather
disturbance working with an unstable airmass will bring mostly
rain showers with some thunderstorms Monday afternoon and early
evening. Expectation is rain will be the major precipitation type
with perhaps some graupel or small soft hail associated with some
of the thunderstorms and perhaps MVFR visibility and ceilings
associated with the precipitation. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 40 50 34 48 33 53 / 60 50 40 40 30 30
Coeur d`Alene 37 49 33 47 31 51 / 80 60 60 50 40 30
Pullman 40 50 36 48 35 53 / 90 70 70 50 40 30
Lewiston 43 53 38 53 37 56 / 90 70 60 40 30 20
Colville 38 55 33 53 31 54 / 90 60 60 50 20 30
Sandpoint 36 48 33 48 32 50 / 70 90 70 60 40 30
Kellogg 37 45 34 44 33 48 / 100 90 80 70 50 30
Moses Lake 38 58 35 56 34 60 / 30 20 10 20 10 20
Wenatchee 40 59 39 58 39 60 / 40 30 10 20 10 20
Omak 38 57 33 55 32 57 / 70 30 20 30 10 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1139 PM CDT SUN MAR 22 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 808 PM CDT SUN MAR 22 2015
RADARS THIS EVENING SHOW A STRONG FGEN BAND OF SNOW FROM CENTRAL
MINNESOTA TO SOUTHWEST WISCONSIN TO NORTHERN ILLINOIS. SHORT WAVE
OVER SOUTHEAST MINNESOTA ALONG THIS BAND WILL PRODUCE A SWATH OF
HEAVY SNOW WITH IT ALONG WITH THE BAND ITSELF. QUESTION FOR
CENTRAL WISCONSIN IS HOW MUCH SNOW ACCUMULATION WILL REACH THE
AREA. DRY FEED OF AIR CONTINUES TO ERODE OR HOLD OF WESTERN
ADVANCEMENT OF SNOW INTO CENTRAL WISCONSIN. HAVE ALREADY DELAYED
ARRIVAL A BIT THROUGH EARLY EVENING. BUT STILL OVERALL THEME OF A
MINOR ACCUMULATION FOR AREAS SOUTHWEST OF A LINE FROM MFI TO OSH
LOOKS REASONABLE FOR TONIGHT SO LITTLE CHANGES LIKELY NEEDED REST
OF TONIGHT.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 244 PM CDT SUN MAR 22 2015
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LIGHT TO
MODERATE SNOW OCCURRING OVER SOUTHEAST MINNESOTA...SOUTHWEST
WISCONSIN...AND NORTHEAST IOWA EARLY THIS AFTERNOON ALONG THE
SOUTHWEST FLANK OF A POLAR AIRMASS. ANOTHER AREA OF SNOW EXISTS
OVER THE EASTERN DAKOTAS AHEAD OF A COMPACT SHORTWAVE TROUGH. DRY
AIR EMANATING FROM A CANADIAN HIGH CENTERED OVER THE GREAT LAKES HAS
PREVENTED THE SNOW FROM REACHING THE GROUND OVER CENTRAL WISCONSIN
DESPITE SOME RETURNS ON RADAR EARLIER. AS THE SHORTWAVE OVER THE
DAKOTAS MOVES EAST...SNOW AND ACCUMULATION CHANCES ARE THE MAIN
FORECAST CONCERNS.
TONIGHT...800-700MB THERMAL GRADIENT WILL CONTINUE TO BE ACTIVE
EARLY THIS EVENING OVER SOUTHWEST WISCONSIN. BUT THE MAIN PUSH OF
SNOW WILL BE EXITING MINNESOTA BY MID TO LATE EVENING AHEAD OF A
SHORTWAVE TROUGH...IN CONJUNCTION WITH MID-LEVEL FGEN ON THE NOSE OF
A 25KT LLJ AND A COUPLED JET STRUCTURE. CENTRAL WISCONSIN WILL BE
ON THE NORTHERN FRINGE OF THE AREA OF SNOW WHERE LOW LEVEL EASTERLY
WINDS WILL BE FEEDING IN DRY AIR. SOUNDINGS BECOME SATURATED ABOVE
750MB BY 06Z ACCORDING TO THE NAM...WHILE THE MESOMODELS AND SREF
ARE SLIGHTLY MORE AGGRESSIVE BRINGING IN PRECIP BY THIS TIME INTO
WOOD COUNTY. AS A RESULT...WILL INCREASE PRECIP CHANCES IN THAT
CENTRAL WISCONSIN AREA IN THE 06-09Z PERIOD. ACCUMULATIONS COULD
REACH UP TO AN INCH IN WOOD COUNTY BUT ONLY A TENTH OR TWO FROM
WAUSAU TO OSHKOSH. THE REST OF THE AREA SHOULD SEE INCREASING
CLOUDS. LOWS RANGING FROM THE UPPER TEENS NORTHEAST TO THE MIDDLE
20S SOUTH.
MONDAY...ANY PRECIP WILL HAVE EXITED CENTRAL WISCONSIN BY THE START
OF THE MORNING BUT CLOUDS WILL TAKE MUCH LONGER TO THIN AS CENTRAL
WISCONSIN WILL BE ON THE NORTHEAST EDGE OF THE BAROCLINIC ZONE.
NORTHEAST WISCONSIN WILL HAVE A MUCH GREATER CHANCE OF CLEARING
DURING THE AFTERNOON. THE COMBINATION OF CLOUDS AND AN EAST WIND
WILL KEEP MAX TEMPS COOL. HIGHS WILL BE RANGING THROUGH THE 30S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 244 PM CDT SUN MAR 22 2015
MAIN CONCERN FOR THIS PACKAGE WILL BE THE SYSTEM TUESDAY NIGHT
AND WEDNESDAY...THEN BELOW NORMAL TEMPERATURES FOR THE END OF
THE WORK WEEK INTO NEXT WEEKEND.
12Z MODELS CONTINUE TO SHOW SIGNIFICANT SYSTEM MOVING ACROSS THE
REGION TUESDAY NIGHT INTO WEDNESDAY. MANY ISSUES TO CONTEND WITH
PRECIPITATION TYPE DUE TO DRY AND COLD EASTERLY FLOW WITH LOW
DEW POINTS TUESDAY AFTERNOON...THEN WARM LAYER ALOFT TUESDAY NIGHT
INTO WEDNESDAY. ONE THING IS FOR SURE...PLENTY OF DRY AIR IN THE
LOW LEVELS TO OVERCOME AS NUMERICAL GUIDANCE INDICATING DEW POINTS
IN THE TEENS TO LOWER 20S. ALOFT...MODELS DIFFER ON HOW FAR NORTH
WARM LAYER WILL GET ON INCREASING SOUTHEAST TO SOUTH WINDS. ALSO...
ANOTHER FACTOR THAT MAY IMPACT PRECIPITATION TYPES WILL BE THE
STEEP MID LEVEL LAPSE RATES (700-500MB) AROUND 6.5 C/KM. EVEN THE
WARM LOCATIONS ACROSS EAST CENTRAL WISCONSIN COULD SEE A MIX OR
START AS SNOW UNTIL WARMER AND MORE MOIST AIR ARRIVES. THESE
ISSUES WILL HAVE AN IMPACT ON SNOW TOTALS...BUT FEEL CONFIDENT THAT
AN ACCUMULATING SNOW WILL OCCUR ACROSS THE NORTH.
PRECIPITATION WILL LINGER INTO WEDNESDAY AS SYSTEM DEPARTS THE REGION.
AN UPPER TROUGH MOVING ACROSS THE REGION WILL BRING A CHANCE OF
RAIN OR SNOW WEDNESDAY NIGHT AND THURSDAY. MAINLY DRY CONDITIONS ARE
EXPECTED INTO SATURDAY THE NEXT CHANCE OF RAIN AND SNOW IS EXPECTED
SATURDAY NIGHT AND SUNDAY.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1139 PM CDT SUN MAR 22 2015
AN UPPER DISTURBANCE WILL TRACK SOUTHWEST OF THE AREA OVERNIGHT.
A NORTHWEST TO SOUTHEAST BAND OF SNOW WILL EXTEND FROM CENTRAL
MINNESOTA TO FAR SOUTHWEST WISCONSIN TO NORTHERN ILLINOIS. SOME
MVFR CIGS WITH LIGHT SNOW MAY WORK INTO PARTS OF CENTRAL WISCONSIN
OR SOUTH OF LINE FROM MFI TO Y50 FOR AT TIME TONIGHT...OTHERWISE
VFR CONDITIONS EXPECTED TONIGHT INTO MONDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........TDH
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS MIAMI FL
1014 AM EDT MON MAR 23 2015
.UPDATE...
COLD FRONT APPROACHING CENTRAL AND SOUTHERN FLORIDA TODAY AND
TONIGHT FROM THE GULF OF MEXICO, WITH UPPER WAVE AHEAD OF IT, MAY
GENERATE SCATTERED SHOWERS ESPECIALLY ACROSS THE NORTHERN HALF OF
THE CWA THIS AFTERNOON. AS PREVIOUSLY MENTIONED, THUNDER CHANCES
LOOK SMALL, WITH MEAGER MIDLEVEL LAPSE RATES. FORECAST IN GOOD
SHAPE AND NO CHANGES NECESSARY.
&&
.PREV DISCUSSION... /ISSUED 800 AM EDT MON MAR 23 2015/
AVIATION...
SURFACE FLOW SHOULD BE GENERALLY SOUTHWEST THROUGH THE DAY AS A
COLD FRONT APPROACHES FROM THE WEST. SHOWERS OUT AHEAD OF THIS
FRONT SHOULD BEGIN MOVING INTO THE TAF SITES DURING THE AFTERNOON
AND EARLY EVENING HOURS. ISOLATED THUNDERSTORMS ARE POSSIBLE BUT
BELIEVE COVERAGE WILL BE RATHER SPARSE AND THEREFORE DID NOT
MENTION IN TAFS FOR NOW. BELIEVE FROPA SHOULD OCCUR AT KAPF AROUND
04Z-06Z AND THE EAST COAST SITES TOWARD THE END OF THIS TAF CYCLE.
PREV DISCUSSION... /ISSUED 422 AM EDT MON MAR 23 2015/
DISCUSSION...
A SURFACE LOW CONTINUES TO DEVELOP ALONG THE FLORIDA PANHANDLE
WITH THE TRAILING COLD FRONT ENTERING THE CENTRAL TO EASTERN GULF.
THE GLOBAL MODEL CONSENSUS CONTINUES TO BRING THIS SYSTEM TO THE
EAST TODAY WITH THE FRONT EXPECTED TO APPROACH SOUTH FLORIDA
AROUND 00Z THIS EVENING THEN ACROSS SOUTH FLORIDA AND ADJACENT
WATERS TONIGHT AND STALL ACROSS THE SOUTHERN TIP OF THE PENINSULA
OR FLORIDA STRAITS TUESDAY MORNING.
FOR TODAY...AS THE AFOREMENTIONED FRONT CONTINUES TO PASS ACROSS
THE EASTERN GULF TODAY CHANCES OF SHOWERS AHEAD OF THE FRONT WILL
CONTINUE THROUGH THE MORNING HOURS INTO THE AFTERNOON...WHEN THE
GREATEST COVERAGE OF SHOWERS IS EXPECTED. THUS FAR SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON...WITH A GENERAL CONSENSUS OF THE GLOBAL MODELS AND SHORT
RANGE ENSEMBLE ALTHOUGH THE HRRR MODEL INDICATES LESS COVERAGE AND
IS SLOWER IN SHOWER DEVELOPMENT. ONLY ISOLATED THUNDERSTORM
ACTIVITY IS FORECAST THIS AFTERNOON WITH THE GUIDANCE CONTINUING
TO SUGGEST THAT MID LEVEL TEMPERATURES...LAPSE RATES AND
INSTABILITY IS NOT SUFFICIENT TO SUPPORT ORGANIZED CONVECTION.
HOWEVER THE GUIDANCE DOES INDICATE THAT THE DEEPER LAYERED
MOISTURE AHEAD OF THE FRONT MAY NOT REACH THE PENINSULA UNTIL THE
AFTERNOON HOURS AND SUFFICIENT DAY TIME HEATING COULD TRIGGER SOME
ISOLATED THUNDERSTORMS. THE FORECAST LOW LEVEL WIND PROFILE INDICATES
A PROFILE SUPPORTIVE OF GUSTY WINDS WITH ANY THUNDERSTORM ACTIVITY
BUT IS NOT EXPECTED TO BE BE AN OVERALL THREAT WITH LOW LEVEL
SHEAR NOT SIGNIFICANT. LASTLY...WITH SOUTHWESTERLY WINDS EXPECTED
ACROSS THE PENINSULA THE EAST COAST SEA BREEZE SHOULD BE
SUPPRESSED THIS AFTERNOON...BUT JUST ALONG THE IMMEDIATE COAST IF
THE WINDS BECOME SOUTHEASTERLY THEN THE LOW LEVEL WIND PROFILE
MIGHT SUPPORT A SHORT LIVED FUNNEL CLOUD BUT CONFIDENCE IS LOW.
FOR TUESDAY...THE BOUNDARY AND ASSOCIATED MOISTURE IS FORECAST TO
STALL ACROSS THE FLORIDA STRAITS OR SOUTHERN TIP OF THE PENINSULA
WITH SOME ISOLATED SHOWERS POSSIBLE BUT MAINLY EXPECTED ACROSS THE
ATLANTIC WATERS.
FOR WEDNESDAY THROUGH FRIDAY...BY WEDNESDAY THE SURFACE AND LOW
LEVEL WINDS ARE FORECAST TO BECOME MORE SOUTHERLY WITH THE
BOUNDARY AND ASSOCIATED MOISTURE LIFTING NORTHWARD WITH MAINLY
AFTERNOON SHOWERS FORECAST THROUGH THIS PERIOD.
FOR THE EXTENDED FORECAST...FOR SEVERAL DAYS A STRONG COLD FRONT
HAS BEEN FORECAST TO AFFECT THE REGION THIS UPCOMING WEEKEND WITH
THE GLOBAL MODELS CONTINUING TO FORECAST THIS SCENARIO.
HOWEVER...WHILE THERE IS STILL GENERAL CONSENSUS THE TIMING OF THE
FRONTAL PASSAGE HAS BEEN SLOWED DOWN AND IS NOW FORECAST TO PASS
ACROSS SOUTH FLORIDA AND REGIONAL WATERS ON SATURDAY THEN EXIT THE
REGION SUNDAY NIGHT...ALMOST A 24 HOUR DIFFERENCE FROM PREVIOUS
GUIDANCE. EXTENDED GUIDANCE INDICATES HIGHS ON SUNDAY ONLY IN THE
LOWER 70S...WILL HAVE TO WAIT AND SEE HOW THIS SCENARIO CHANGES IN
FUTURE GUIDANCE.
MARINE...
ISOLATED THUNDERSTORMS ARE FORECAST ACROSS THE REGIONAL WATERS FOR
THIS AFTERNOON AND EARLY EVENING HOURS. IN GENERAL WINDS FORECAST
TO BE 15 KNOTS OR LESS THROUGH MID-WEEK WITH SEAS REMAINING WELL
BELOW ADVISORY LEVELS. WITH THE FORECAST PASSAGE OF A STRONG COLD
FRONT THIS UPCOMING WEEKEND SEAS COULD REACH NEAR ADVISORY
LEVELS...BUT TIMING IS DIFFICULT WITH VARYING GUIDANCE AND WILL
HAVE TO WAIT FOR FURTHER GUIDANCE CONSENSUS FOR TIMING PURPOSES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 85 69 87 70 / 40 30 10 10
FORT LAUDERDALE 85 71 84 71 / 30 20 10 10
MIAMI 86 71 87 71 / 30 20 10 10
NAPLES 83 69 84 67 / 40 20 10 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS MIAMI FL
800 AM EDT MON MAR 23 2015
.AVIATION...
SURFACE FLOW SHOULD BE GENERALLY SOUTHWEST THROUGH THE DAY AS A
COLD FRONT APPROACHES FROM THE WEST. SHOWERS OUT AHEAD OF THIS
FRONT SHOULD BEGIN MOVING INTO THE TAF SITES DURING THE AFTERNOON
AND EARLY EVENING HOURS. ISOLATED THUNDERSTORMS ARE POSSIBLE BUT
BELIEVE COVERAGE WILL BE RATHER SPARSE AND THEREFORE DID NOT
MENTION IN TAFS FOR NOW. BELIEVE FROPA SHOULD OCCUR AT KAPF AROUND
04Z-06Z AND THE EAST COAST SITES TOWARD THE END OF THIS TAF CYCLE.
&&
.PREV DISCUSSION... /ISSUED 422 AM EDT MON MAR 23 2015/
DISCUSSION...
A SURFACE LOW CONTINUES TO DEVELOP ALONG THE FLORIDA PANHANDLE
WITH THE TRAILING COLD FRONT ENTERING THE CENTRAL TO EASTERN GULF.
THE GLOBAL MODEL CONSENSUS CONTINUES TO BRING THIS SYSTEM TO THE
EAST TODAY WITH THE FRONT EXPECTED TO APPROACH SOUTH FLORIDA
AROUND 00Z THIS EVENING THEN ACROSS SOUTH FLORIDA AND ADJACENT
WATERS TONIGHT AND STALL ACROSS THE SOUTHERN TIP OF THE PENINSULA
OR FLORIDA STRAITS TUESDAY MORNING.
FOR TODAY...AS THE AFOREMENTIONED FRONT CONTINUES TO PASS ACROSS
THE EASTERN GULF TODAY CHANCES OF SHOWERS AHEAD OF THE FRONT WILL
CONTINUE THROUGH THE MORNING HOURS INTO THE AFTERNOON...WHEN THE
GREATEST COVERAGE OF SHOWERS IS EXPECTED. THUS FAR SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON...WITH A GENERAL CONSENSUS OF THE GLOBAL MODELS AND SHORT
RANGE ENSEMBLE ALTHOUGH THE HRRR MODEL INDICATES LESS COVERAGE AND
IS SLOWER IN SHOWER DEVELOPMENT. ONLY ISOLATED THUNDERSTORM
ACTIVITY IS FORECAST THIS AFTERNOON WITH THE GUIDANCE CONTINUING
TO SUGGEST THAT MID LEVEL TEMPERATURES...LAPSE RATES AND
INSTABILITY IS NOT SUFFICIENT TO SUPPORT ORGANIZED CONVECTION.
HOWEVER THE GUIDANCE DOES INDICATE THAT THE DEEPER LAYERED
MOISTURE AHEAD OF THE FRONT MAY NOT REACH THE PENINSULA UNTIL THE
AFTERNOON HOURS AND SUFFICIENT DAY TIME HEATING COULD TRIGGER SOME
ISOLATED THUNDERSTORMS. THE FORECAST LOW LEVEL WIND PROFILE INDICATES
A PROFILE SUPPORTIVE OF GUSTY WINDS WITH ANY THUNDERSTORM ACTIVITY
BUT IS NOT EXPECTED TO BE BE AN OVERALL THREAT WITH LOW LEVEL
SHEAR NOT SIGNIFICANT. LASTLY...WITH SOUTHWESTERLY WINDS EXPECTED
ACROSS THE PENINSULA THE EAST COAST SEA BREEZE SHOULD BE
SUPPRESSED THIS AFTERNOON...BUT JUST ALONG THE IMMEDIATE COAST IF
THE WINDS BECOME SOUTHEASTERLY THEN THE LOW LEVEL WIND PROFILE
MIGHT SUPPORT A SHORT LIVED FUNNEL CLOUD BUT CONFIDENCE IS LOW.
FOR TUESDAY...THE BOUNDARY AND ASSOCIATED MOISTURE IS FORECAST TO
STALL ACROSS THE FLORIDA STRAITS OR SOUTHERN TIP OF THE PENINSULA
WITH SOME ISOLATED SHOWERS POSSIBLE BUT MAINLY EXPECTED ACROSS THE
ATLANTIC WATERS.
FOR WEDNESDAY THROUGH FRIDAY...BY WEDNESDAY THE SURFACE AND LOW
LEVEL WINDS ARE FORECAST TO BECOME MORE SOUTHERLY WITH THE
BOUNDARY AND ASSOCIATED MOISTURE LIFTING NORTHWARD WITH MAINLY
AFTERNOON SHOWERS FORECAST THROUGH THIS PERIOD.
FOR THE EXTENDED FORECAST...FOR SEVERAL DAYS A STRONG COLD FRONT
HAS BEEN FORECAST TO AFFECT THE REGION THIS UPCOMING WEEKEND WITH
THE GLOBAL MODELS CONTINUING TO FORECAST THIS SCENARIO.
HOWEVER...WHILE THERE IS STILL GENERAL CONSENSUS THE TIMING OF THE
FRONTAL PASSAGE HAS BEEN SLOWED DOWN AND IS NOW FORECAST TO PASS
ACROSS SOUTH FLORIDA AND REGIONAL WATERS ON SATURDAY THEN EXIT THE
REGION SUNDAY NIGHT...ALMOST A 24 HOUR DIFFERENCE FROM PREVIOUS
GUIDANCE. EXTENDED GUIDANCE INDICATES HIGHS ON SUNDAY ONLY IN THE
LOWER 70S...WILL HAVE TO WAIT AND SEE HOW THIS SCENARIO CHANGES IN
FUTURE GUIDANCE.
MARINE...
ISOLATED THUNDERSTORMS ARE FORECAST ACROSS THE REGIONAL WATERS FOR
THIS AFTERNOON AND EARLY EVENING HOURS. IN GENERAL WINDS FORECAST
TO BE 15 KNOTS OR LESS THROUGH MID-WEEK WITH SEAS REMAINING WELL
BELOW ADVISORY LEVELS. WITH THE FORECAST PASSAGE OF A STRONG COLD
FRONT THIS UPCOMING WEEKEND SEAS COULD REACH NEAR ADVISORY
LEVELS...BUT TIMING IS DIFFICULT WITH VARYING GUIDANCE AND WILL
HAVE TO WAIT FOR FURTHER GUIDANCE CONSENSUS FOR TIMING PURPOSES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 85 69 87 70 / 40 30 10 10
FORT LAUDERDALE 85 71 84 71 / 30 20 10 10
MIAMI 86 71 87 71 / 30 20 10 10
NAPLES 83 69 84 67 / 40 20 10 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....60/BD
AVIATION...10/CD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1022 AM EDT MON MAR 23 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 232 AM EDT MON MAR 23 2015
AN ACTIVE WEATHER PATTERN IS SET FOR THE NEXT FEW DAYS AS SEVERAL
SYSTEMS WILL PUSH THROUGH THE REGION GIVING US SEVERAL CHANCES FOR
PRECIPITATION THROUGH THE MIDDLE OF THE WORK WEEK.
A WEAK UPPER DISTURBANCES IS EXPECTED TO PUSH ACROSS THE NORTHERN
PARTS OF CENTRAL INDIANA TODAY. THIS MAY RESULT IN A BRIEF PERIOD OF
MIXED PRECIPITATION MAINLY IN THE LAFAYETTE...KOKOMO AND MUNCIE
AREAS.
A LOW PRESSURE SYSTEM WILL PUSH INTO THE GREAT LAKES FROM THE
PLAINS STATES ON TUESDAY NIGHT. THIS WILL BRING ANOTHER CHANCE FOR
RAIN TO MAINLY THE NORTHERN PARTS OF CENTRAL INDIANA TOWARD
WEDNESDAY MORNING.
FINALLY A STRONGER LOW AND COLD FRONT IS EXPECTED TO PASS ACROSS
CENTRAL INDIANA ON WEDNESDAY NIGHT...BRINGING RAIN AND EVEN
POSSIBLY A FEW THUNDERSTORMS.
COLDER BUT DRY WEATHER LOOKS TO SETTLE ACROSS THE THE OHIO VALLEY
IN THE WAKE OF THE COLD FRONT FOR THE END OF THE WORK WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 1022 AM EDT MON MAR 23 2015
ADJUSTMENTS REQUIRED TO POPS TO BRING THINGS INTO THE NORTHWEST A
BIT EARLIER...ALTHOUGH INITIAL ECHOES WILL LIKELY NOT REACH THE
GROUND.
WETBULB EFFECTS WILL INITIALLY ALLOW THINGS TO FALL AS SNOW. WILL
TRANSITION MORE TO A MIX ACROSS OUR NORTH AND RAIN ELSEWHERE AS THE
DAY WEARS ON. COULD SEE A DUSTING ACROSS OUR FAR NORTH...BUT GROUND
IS WARM AND LIKELY WILL NOT ALLOW ANYTHING TO STICK AROUND LONG.
ADDITIONALLY...TIGHTENED MAX TEMP GRADIENT ACROSS THE AREA AND
LOWERED TEMPS A BIT ACROSS THE NORTH OWING TO THE COOLING LIKELY TO
OCCUR AS PRECIPITATION BEGINS. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 232 AM EDT MON MAR 23 2015
SURFACE ANALYSIS EARLY THIS MORNING SHOWS A WEAK AREA OF LOW
PRESSURE OVER NW MISSOURI. DRY EASTERLY FLOW WAS IN PLACE ACROSS
CENTRAL INDIANA AND DEW POINT TEMPS WERE IN THE TEENS. RADAR
SHOWED AN AREA OF SNOW SHOWERS OVER SOUTHEASTERN WISCONSIN.
MAIN FORECAST CHALLENGE TODAY WILL BE POPS.
MODELS SHOW WEAK SHORT WAVE PROVIDING DYNAMICS OVER WISCONSIN
POISED TO PUSH ACROSS NORTHERN INDIANA LATE THIS AFTERNOON AMID
THE NW FLOW ALOFT. FORECAST SOUNDINGS SHOW MID LEVEL SATURATION
ACROSS THE NORTHERN PARTS OF THE FORECAST AREA WITH DRY...COLD AIR
ENTRENCHED AT THE SURFACE. VIRGA AND EVAPORATIONAL COOLING SHOULD
EVENTUALLY SATURATED THE LOWER LEVELS...HOWEVER MOISTURE APPEARS
LIMITED. THUS ONLY SOME LIGHT PRECIP WILL BE EXPECT MAINLY DURING
THE AFTERNOON HOURS ACROSS THE NORTH. THIS ALSO AGREES WITH RAPID
REFRESH PRECIP PROJECTIONS.
GIVEN THE STEEP INVERSIONS IN THE LOWEST LEVELS OF THE FORECAST
SOUNDINGS...PRECIP TYPE APPEARS TO BE A FACTOR. WITH MOST OF THE
SOUNDING BELOW FREEZING...ANY PRECIP SHOULD BEGIN AS SNOW...BUT IF
TEMPS ARE ABOVE FREEZING IN THE LOWER LEVELS...ENOUGH MELTING
SHOULD OCCUR FOR SOME RAIN. ESPECIALLY SINCE SURFACE TEMPS SHOULD
REMAIN ABOVE FREEZING THROUGH THE AFTERNOON. MAVMOS TEMP AT LAF
APPEAR TOO COLD...WITH HOURLYS SUGGESTING MID 20S AT 06Z...WHILE
CURRENTS ARE IN THE MIDDLE 30S. WITH NO MID 20S UPSTREAM...WILL
TREND MOST PRECIP TYPE TOWARD RAIN...WITH A FEW ISOLATED FLAKES
POSSIBLE. THUS WILL USE A RAIN SNOW MIX TODAY. A BLEND OF MAVMOS
AND METMOS TEMPS LOOKS TO WORK FINE...RESULTING MAINLY IN WARMER
VALUES THAN MAVMOS...WHICH HAS BEEN THE CASE THE PAST FEW DAYS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 232 AM EDT MON MAR 23 2015
ACTIVE WEATHER PATTERN IN PLAY AS A SERIES OF SHORT WAVES WILL PASS
THROUGH THE REGION THROUGH WEDNESDAY. THE QUICK MOVING UPPER WAVE
DEPARTS TONIGHT AS RIDGING ONCE AGAIN RESUMES IT/S PRESENCE ACROSS
THE REGION TONIGHT. FORECAST SOUNDINGS SHOW GOOD MID LEVEL DRYING
INDICATING SUBSIDENCE WHILE NORTHEAST SURFACE FLOW AND CLOUDS
CONTINUE TO PERSIST. WILL TREND TOWARD A DRY FORECAST THEN ALONG
WITH LOWS WARMER THAN MAVMOS.
ON TUESDAY...STRONG WARM AIR ADVECTION RESUMES DURING THE DAY AS
LOW PRESSURE DEEPENS OVER THE PLAINS STATES AND SOUTHERLY FLOW
RESUMES ALOFT ACROSS THE OHIO VALLEY. AT THE SURFACE STRONG HIGH
PRESSURE REMAINS OVER SE ONTARIO...PUMPING DRY AND COOL AIR TOWARD
INDIANA. THIS SHOULD MAKE FOR A CONTINUED OVERRUNNING
SITUATION...WITH CLOUDS ALOFT. MODELS THEN SUGGEST AN INITIAL WEAK
WAVE ARRIVING BUY TUESDAY AFTERNOON...HOWEVER THE MUCH STRONGER
AND MORE ORGANIZED...NEGATIVELY TILTED WAVE APPEARS TO ARRIVE ON
TUESDAY NIGHT...PUSH NORTHEAST INTO MICHIGAN. WITH BEST DYNAMICS
ARRIVING ON TUESDAY AND WILL FOCUS MAIN PRECIP CHANCES ON TUESDAY
NIGHT...BUT MAY NEED TO INCLUDE SOME LOW CHANCES DURING THE
AFTERNOON ACROSS THE WESTERN PARTS OF THE STATE. GIVEN THE
OVERRUNNING SITUATION AND MAVMOS RUNNING TOO COOL...WILL TREND
HIGHS WARMER THAN MAVMOS TUESDAY AND LOW WARMER ON TUESDAY NIGHT
AS PRECIP WILL BE EXPECTED AS THE STRONGER SHORT WAVE PUSHES
NORTHEAST TO TOWARD MICHIGAN.
AFTER THIS SYSTEM DEPARTS ON TUESDAY NIGHT..ANOTHER BRIEF BREAK IS
EXPECTED ON WEDNESDAY DRY AIR WORKS INTO THE STATE FROM THE
SOUTHWEST. ALOFT ANOTHER DEEPER WAVE IS EXPECTED TO DIG OUT OF THE
PLAINS STATES AND PUSH TOWARD THE OHIO VALLEY FOR WEDNESDAY
NIGHT. WITH SUBSIDENCE IN PLACE AMID WARM AIR ADVECTION AND A DRY
FORECAST COLUMN WILL TREND TOWARD A PARTLY SUNNY WEDNESDAY AND
WILL TREND TEMPS WARMER THAN MAVMOS.
AS THE STRONG WAVE PUSHES ACROSS THE STATE ON WEDNESDAY NIGHT
ALONG WITH A STRONGER COLD FRONT...FAVORABLE CONDITIONS FOR PRECIP
APPEAR IN PLAY...INCLUDING A PERIOD OF WARMER AND MORE MOIST
SOUTHERLY FLOW AHEAD OF THE COLD FRONT. WILL TREND POPS HIGHER ON
WEDNESDAY NIGHT AND TREND LOWS WARMER GIVEN THE EXPECTED PRECIP
AND CLOUDS. THUNDER ON WEDNESDAY NIGHT LOOKS QUITE REASONABLE AS
FORECAST SOUNDINGS AT THIS TIME SHOW ATTAINABLE CONVECTIVE TEMPS
IN THE MIDDLE 50S...STEEP LAPSE RATES AND CAPES OVER 1000 J/KG.
GUESS SPRING IS HERE.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
ISSUED AT 321 AM EDT MON MAR 23 2015
A COLD FRONT WILL BE EXITING THE AREA BY THURSDAY MORNING BUT SOME
UPPER FORCING WILL LAG BEHIND IT...KEEPING CHANCES FOR RAIN IN THE
FORECAST FOR THURSDAY. BY THURSDAY NIGHT SURFACE HIGH PRESSURE
STARTS TO BUILD IN FROM THE NORTHWEST. HOWEVER CYCLONIC UPPER FLOW
WILL CONTINUE THROUGH FRIDAY UNTIL THE UPPER TROUGH AXIS MOVES
THROUGH THE AREA. THIS FEATURE WILL KEEP A SLIGHT CHANCE FOR
PRECIPITATION GOING FOR THURSDAY NIGHT AND FRIDAY. WITH COLD
ADVECTION TAKING PLACE AT ALL LEVELS WILL SEE SLIGHT CHANCE FOR RAIN
EARLY THURSDAY NIGHT CHANGE OVER TO A SLIGHT CHANCE FOR SNOW
LATE...AND A MIX WILL BE POSSIBLE INTO FRIDAY MORNING. ARCTIC HIGH
PRESSURE MOVING IN WILL BRING DECREASING CLOUD COVER AND MUCH COLDER
TEMPERATURES WITH HIGHS ON FRIDAY AND SATURDAY IN THE UPPER 30S TO
MID 40S AND LOWS FRIDAY NIGHT ONLY IN THE LOW TO MID 20S. SUNDAY THE
NEXT LOW PRESSURE SYSTEM WILL APPROACH AND BRING IN RAIN CHANCES
THROUGH SUNDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR 231500Z IND TAF UPDATE/...
ISSUED AT 1018 AM EDT MON MAR 23 2015
NO CHANGES NEEDED TO THE TAF.
PREVIOUS DISCUSSION FOLLOWS...
PRECIPITATION AND LOWER CEILINGS WILL START TO MOVE INTO THE SITES
LATER TODAY FROM THE NORTHWEST. BASED ON UPSTREAM OBSERVATIONS AND
AVAILABLE GUIDANCE /ESPECIALLY THE HRRR/ THINK KLAF WILL MOST LIKELY
HAVE SNOW FOR A FEW HOURS...WITH A RAIN/SNOW MIX POSSIBLE AT KIND
AND RAIN FURTHER SOUTH. WILL TEMPO THESE IN AND USED HRRR FOR
TIMING...ARRIVING IN KLAF AFTER 16Z AND FINALLY IN KBMG AROUND 20Z.
THE SOUTHERN SITES MAY NOT SEE FLIGHT RESTRICTIONS WITH THESE
SHOWERS AND WILL KEEP THEM VFR FOR NOW. AT KIND THOUGH EXPECT MVFR
TO DEVELOP WITH THE PRECIP MOVING THROUGH AND AT KLAF COULD SEE IFR
WITH THE INCREASED LIKELIHOOD OF SNOW. WINDS WILL CONTINUE TO HAVE
AN EASTERLY COMPONENT /MAINLY ENE/ THROUGH THE DAY AND RUN AROUND
8-12 KTS. COULD SEE SOME GUSTS BUT NOT STRONG ENOUGH OR WIDESPREAD
ENOUGH TO INCLUDE AT THIS TIME.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA/NIELD
SHORT TERM...PUMA
LONG TERM...CP
AVIATION...CP/MK
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1018 AM EDT MON MAR 23 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 232 AM EDT MON MAR 23 2015
AN ACTIVE WEATHER PATTERN IS SET FOR THE NEXT FEW DAYS AS SEVERAL
SYSTEMS WILL PUSH THROUGH THE REGION GIVING US SEVERAL CHANCES FOR
PRECIPITATION THROUGH THE MIDDLE OF THE WORK WEEK.
A WEAK UPPER DISTURBANCES IS EXPECTED TO PUSH ACROSS THE NORTHERN
PARTS OF CENTRAL INDIANA TODAY. THIS MAY RESULT IN A BRIEF PERIOD OF
MIXED PRECIPITATION MAINLY IN THE LAFAYETTE...KOKOMO AND MUNCIE
AREAS.
A LOW PRESSURE SYSTEM WILL PUSH INTO THE GREAT LAKES FROM THE
PLAINS STATES ON TUESDAY NIGHT. THIS WILL BRING ANOTHER CHANCE FOR
RAIN TO MAINLY THE NORTHERN PARTS OF CENTRAL INDIANA TOWARD
WEDNESDAY MORNING.
FINALLY A STRONGER LOW AND COLD FRONT IS EXPECTED TO PASS ACROSS
CENTRAL INDIANA ON WEDNESDAY NIGHT...BRINGING RAIN AND EVEN
POSSIBLY A FEW THUNDERSTORMS.
COLDER BUT DRY WEATHER LOOKS TO SETTLE ACROSS THE THE OHIO VALLEY
IN THE WAKE OF THE COLD FRONT FOR THE END OF THE WORK WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 232 AM EDT MON MAR 23 2015
SURFACE ANALYSIS EARLY THIS MORNING SHOWS A WEAK AREA OF LOW
PRESSURE OVER NW MISSOURI. DRY EASTERLY FLOW WAS IN PLACE ACROSS
CENTRAL INDIANA AND DEW POINT TEMPS WERE IN THE TEENS. RADAR
SHOWED AN AREA OF SNOW SHOWERS OVER SOUTHEASTERN WISCONSIN.
MAIN FORECAST CHALLENGE TODAY WILL BE POPS.
MODELS SHOW WEAK SHORT WAVE PROVIDING DYNAMICS OVER WISCONSIN
POISED TO PUSH ACROSS NORTHERN INDIANA LATE THIS AFTERNOON AMID
THE NW FLOW ALOFT. FORECAST SOUNDINGS SHOW MID LEVEL SATURATION
ACROSS THE NORTHERN PARTS OF THE FORECAST AREA WITH DRY...COLD AIR
ENTRENCHED AT THE SURFACE. VIRGA AND EVAPORATIONAL COOLING SHOULD
EVENTUALLY SATURATED THE LOWER LEVELS...HOWEVER MOISTURE APPEARS
LIMITED. THUS ONLY SOME LIGHT PRECIP WILL BE EXPECT MAINLY DURING
THE AFTERNOON HOURS ACROSS THE NORTH. THIS ALSO AGREES WITH RAPID
REFRESH PRECIP PROJECTIONS.
GIVEN THE STEEP INVERSIONS IN THE LOWEST LEVELS OF THE FORECAST
SOUNDINGS...PRECIP TYPE APPEARS TO BE A FACTOR. WITH MOST OF THE
SOUNDING BELOW FREEZING...ANY PRECIP SHOULD BEGIN AS SNOW...BUT IF
TEMPS ARE ABOVE FREEZING IN THE LOWER LEVELS...ENOUGH MELTING
SHOULD OCCUR FOR SOME RAIN. ESPECIALLY SINCE SURFACE TEMPS SHOULD
REMAIN ABOVE FREEZING THROUGH THE AFTERNOON. MAVMOS TEMP AT LAF
APPEAR TOO COLD...WITH HOURLYS SUGGESTING MID 20S AT 06Z...WHILE
CURRENTS ARE IN THE MIDDLE 30S. WITH NO MID 20S UPSTREAM...WILL
TREND MOST PRECIP TYPE TOWARD RAIN...WITH A FEW ISOLATED FLAKES
POSSIBLE. THUS WILL USE A RAIN SNOW MIX TODAY. A BLEND OF MAVMOS
AND METMOS TEMPS LOOKS TO WORK FINE...RESULTING MAINLY IN WARMER
VALUES THAN MAVMOS...WHICH HAS BEEN THE CASE THE PAST FEW DAYS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 232 AM EDT MON MAR 23 2015
ACTIVE WEATHER PATTERN IN PLAY AS A SERIES OF SHORT WAVES WILL PASS
THROUGH THE REGION THROUGH WEDNESDAY. THE QUICK MOVING UPPER WAVE
DEPARTS TONIGHT AS RIDGING ONCE AGAIN RESUMES IT/S PRESENCE ACROSS
THE REGION TONIGHT. FORECAST SOUNDINGS SHOW GOOD MID LEVEL DRYING
INDICATING SUBSIDENCE WHILE NORTHEAST SURFACE FLOW AND CLOUDS
CONTINUE TO PERSIST. WILL TREND TOWARD A DRY FORECAST THEN ALONG
WITH LOWS WARMER THAN MAVMOS.
ON TUESDAY...STRONG WARM AIR ADVECTION RESUMES DURING THE DAY AS
LOW PRESSURE DEEPENS OVER THE PLAINS STATES AND SOUTHERLY FLOW
RESUMES ALOFT ACROSS THE OHIO VALLEY. AT THE SURFACE STRONG HIGH
PRESSURE REMAINS OVER SE ONTARIO...PUMPING DRY AND COOL AIR TOWARD
INDIANA. THIS SHOULD MAKE FOR A CONTINUED OVERRUNNING
SITUATION...WITH CLOUDS ALOFT. MODELS THEN SUGGEST AN INITIAL WEAK
WAVE ARRIVING BUY TUESDAY AFTERNOON...HOWEVER THE MUCH STRONGER
AND MORE ORGANIZED...NEGATIVELY TILTED WAVE APPEARS TO ARRIVE ON
TUESDAY NIGHT...PUSH NORTHEAST INTO MICHIGAN. WITH BEST DYNAMICS
ARRIVING ON TUESDAY AND WILL FOCUS MAIN PRECIP CHANCES ON TUESDAY
NIGHT...BUT MAY NEED TO INCLUDE SOME LOW CHANCES DURING THE
AFTERNOON ACROSS THE WESTERN PARTS OF THE STATE. GIVEN THE
OVERRUNNING SITUATION AND MAVMOS RUNNING TOO COOL...WILL TREND
HIGHS WARMER THAN MAVMOS TUESDAY AND LOW WARMER ON TUESDAY NIGHT
AS PRECIP WILL BE EXPECTED AS THE STRONGER SHORT WAVE PUSHES
NORTHEAST TO TOWARD MICHIGAN.
AFTER THIS SYSTEM DEPARTS ON TUESDAY NIGHT..ANOTHER BRIEF BREAK IS
EXPECTED ON WEDNESDAY DRY AIR WORKS INTO THE STATE FROM THE
SOUTHWEST. ALOFT ANOTHER DEEPER WAVE IS EXPECTED TO DIG OUT OF THE
PLAINS STATES AND PUSH TOWARD THE OHIO VALLEY FOR WEDNESDAY
NIGHT. WITH SUBSIDENCE IN PLACE AMID WARM AIR ADVECTION AND A DRY
FORECAST COLUMN WILL TREND TOWARD A PARTLY SUNNY WEDNESDAY AND
WILL TREND TEMPS WARMER THAN MAVMOS.
AS THE STRONG WAVE PUSHES ACROSS THE STATE ON WEDNESDAY NIGHT
ALONG WITH A STRONGER COLD FRONT...FAVORABLE CONDITIONS FOR PRECIP
APPEAR IN PLAY...INCLUDING A PERIOD OF WARMER AND MORE MOIST
SOUTHERLY FLOW AHEAD OF THE COLD FRONT. WILL TREND POPS HIGHER ON
WEDNESDAY NIGHT AND TREND LOWS WARMER GIVEN THE EXPECTED PRECIP
AND CLOUDS. THUNDER ON WEDNESDAY NIGHT LOOKS QUITE REASONABLE AS
FORECAST SOUNDINGS AT THIS TIME SHOW ATTAINABLE CONVECTIVE TEMPS
IN THE MIDDLE 50S...STEEP LAPSE RATES AND CAPES OVER 1000 J/KG.
GUESS SPRING IS HERE.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
ISSUED AT 321 AM EDT MON MAR 23 2015
A COLD FRONT WILL BE EXITING THE AREA BY THURSDAY MORNING BUT SOME
UPPER FORCING WILL LAG BEHIND IT...KEEPING CHANCES FOR RAIN IN THE
FORECAST FOR THURSDAY. BY THURSDAY NIGHT SURFACE HIGH PRESSURE
STARTS TO BUILD IN FROM THE NORTHWEST. HOWEVER CYCLONIC UPPER FLOW
WILL CONTINUE THROUGH FRIDAY UNTIL THE UPPER TROUGH AXIS MOVES
THROUGH THE AREA. THIS FEATURE WILL KEEP A SLIGHT CHANCE FOR
PRECIPITATION GOING FOR THURSDAY NIGHT AND FRIDAY. WITH COLD
ADVECTION TAKING PLACE AT ALL LEVELS WILL SEE SLIGHT CHANCE FOR RAIN
EARLY THURSDAY NIGHT CHANGE OVER TO A SLIGHT CHANCE FOR SNOW
LATE...AND A MIX WILL BE POSSIBLE INTO FRIDAY MORNING. ARCTIC HIGH
PRESSURE MOVING IN WILL BRING DECREASING CLOUD COVER AND MUCH COLDER
TEMPERATURES WITH HIGHS ON FRIDAY AND SATURDAY IN THE UPPER 30S TO
MID 40S AND LOWS FRIDAY NIGHT ONLY IN THE LOW TO MID 20S. SUNDAY THE
NEXT LOW PRESSURE SYSTEM WILL APPROACH AND BRING IN RAIN CHANCES
THROUGH SUNDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR 231500Z IND TAF UPDATE/...
ISSUED AT 1018 AM EDT MON MAR 23 2015
NO CHANGES NEEDED TO THE TAF.
PREVIOUS DISCUSSION FOLLOWS...
PRECIPITATION AND LOWER CEILINGS WILL START TO MOVE INTO THE SITES
LATER TODAY FROM THE NORTHWEST. BASED ON UPSTREAM OBSERVATIONS AND
AVAILABLE GUIDANCE /ESPECIALLY THE HRRR/ THINK KLAF WILL MOST LIKELY
HAVE SNOW FOR A FEW HOURS...WITH A RAIN/SNOW MIX POSSIBLE AT KIND
AND RAIN FURTHER SOUTH. WILL TEMPO THESE IN AND USED HRRR FOR
TIMING...ARRIVING IN KLAF AFTER 16Z AND FINALLY IN KBMG AROUND 20Z.
THE SOUTHERN SITES MAY NOT SEE FLIGHT RESTRICTIONS WITH THESE
SHOWERS AND WILL KEEP THEM VFR FOR NOW. AT KIND THOUGH EXPECT MVFR
TO DEVELOP WITH THE PRECIP MOVING THROUGH AND AT KLAF COULD SEE IFR
WITH THE INCREASED LIKELIHOOD OF SNOW. WINDS WILL CONTINUE TO HAVE
AN EASTERLY COMPONENT /MAINLY ENE/ THROUGH THE DAY AND RUN AROUND
8-12 KTS. COULD SEE SOME GUSTS BUT NOT STRONG ENOUGH OR WIDESPREAD
ENOUGH TO INCLUDE AT THIS TIME.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM....CP
AVIATION...CP/MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
645 AM EDT MON MAR 23 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 232 AM EDT MON MAR 23 2015
AN ACTIVE WEATHER PATTERN IS SET FOR THE NEXT FEW DAYS AS SEVERAL
SYSTEMS WILL PUSH THROUGH THE REGION GIVING US SEVERAL CHANCES FOR
PRECIPITATION THROUGH THE MIDDLE OF THE WORK WEEK.
A WEAK UPPER DISTURBANCES IS EXPECTED TO PUSH ACROSS THE NORTHERN
PARTS OF CENTRAL INDIANA TODAY. THIS MAY RESULT IN A BRIEF PERIOD OF
MIXED PRECIPITATION MAINLY IN THE LAFAYETTE...KOKOMO AND MUNCIE
AREAS.
A LOW PRESSURE SYSTEM WILL PUSH INTO THE GREAT LAKES FROM THE
PLAINS STATES ON TUESDAY NIGHT. THIS WILL BRING ANOTHER CHANCE FOR
RAIN TO MAINLY THE NORTHERN PARTS OF CENTRAL INDIANA TOWARD
WEDNESDAY MORNING.
FINALLY A STRONGER LOW AND COLD FRONT IS EXPECTED TO PASS ACROSS
CENTRAL INDIANA ON WEDNESDAY NIGHT...BRINGING RAIN AND EVEN
POSSIBLY A FEW THUNDERSTORMS.
COLDER BUT DRY WEATHER LOOKS TO SETTLE ACROSS THE THE OHIO VALLEY
IN THE WAKE OF THE COLD FRONT FOR THE END OF THE WORK WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 232 AM EDT MON MAR 23 2015
SURFACE ANALYSIS EARLY THIS MORNING SHOWS A WEAK AREA OF LOW
PRESSURE OVER NW MISSOURI. DRY EASTERLY FLOW WAS IN PLACE ACROSS
CENTRAL INDIANA AND DEW POINT TEMPS WERE IN THE TEENS. RADAR
SHOWED AN AREA OF SNOW SHOWERS OVER SOUTHEASTERN WISCONSIN.
MAIN FORECAST CHALLENGE TODAY WILL BE POPS.
MODELS SHOW WEAK SHORT WAVE PROVIDING DYNAMICS OVER WISCONSIN
POISED TO PUSH ACROSS NORTHERN INDIANA LATE THIS AFTERNOON AMID
THE NW FLOW ALOFT. FORECAST SOUNDINGS SHOW MID LEVEL SATURATION
ACROSS THE NORTHERN PARTS OF THE FORECAST AREA WITH DRY...COLD AIR
ENTRENCHED AT THE SURFACE. VIRGA AND EVAPORATIONAL COOLING SHOULD
EVENTUALLY SATURATED THE LOWER LEVELS...HOWEVER MOISTURE APPEARS
LIMITED. THUS ONLY SOME LIGHT PRECIP WILL BE EXPECT MAINLY DURING
THE AFTERNOON HOURS ACROSS THE NORTH. THIS ALSO AGREES WITH RAPID
REFRESH PRECIP PROJECTIONS.
GIVEN THE STEEP INVERSIONS IN THE LOWEST LEVELS OF THE FORECAST
SOUNDINGS...PRECIP TYPE APPEARS TO BE A FACTOR. WITH MOST OF THE
SOUNDING BELOW FREEZING...ANY PRECIP SHOULD BEGIN AS SNOW...BUT IF
TEMPS ARE ABOVE FREEZING IN THE LOWER LEVELS...ENOUGH MELTING
SHOULD OCCUR FOR SOME RAIN. ESPECIALLY SINCE SURFACE TEMPS SHOULD
REMAIN ABOVE FREEZING THROUGH THE AFTERNOON. MAVMOS TEMP AT LAF
APPEAR TOO COLD...WITH HOURLYS SUGGESTING MID 20S AT 06Z...WHILE
CURRENTS ARE IN THE MIDDLE 30S. WITH NO MID 20S UPSTREAM...WILL
TREND MOST PRECIP TYPE TOWARD RAIN...WITH A FEW ISOLATED FLAKES
POSSIBLE. THUS WILL USE A RAIN SNOW MIX TODAY. A BLEND OF MAVMOS
AND METMOS TEMPS LOOKS TO WORK FINE...RESULTING MAINLY IN WARMER
VALUES THAN MAVMOS...WHICH HAS BEEN THE CASE THE PAST FEW DAYS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 232 AM EDT MON MAR 23 2015
ACTIVE WEATHER PATTERN IN PLAY AS A SERIES OF SHORT WAVES WILL PASS
THROUGH THE REGION THROUGH WEDNESDAY. THE QUICK MOVING UPPER WAVE
DEPARTS TONIGHT AS RIDGING ONCE AGAIN RESUMES IT/S PRESENCE ACROSS
THE REGION TONIGHT. FORECAST SOUNDINGS SHOW GOOD MID LEVEL DRYING
INDICATING SUBSIDENCE WHILE NORTHEAST SURFACE FLOW AND CLOUDS
CONTINUE TO PERSIST. WILL TREND TOWARD A DRY FORECAST THEN ALONG
WITH LOWS WARMER THAN MAVMOS.
ON TUESDAY...STRONG WARM AIR ADVECTION RESUMES DURING THE DAY AS
LOW PRESSURE DEEPENS OVER THE PLAINS STATES AND SOUTHERLY FLOW
RESUMES ALOFT ACROSS THE OHIO VALLEY. AT THE SURFACE STRONG HIGH
PRESSURE REMAINS OVER SE ONTARIO...PUMPING DRY AND COOL AIR TOWARD
INDIANA. THIS SHOULD MAKE FOR A CONTINUED OVERRUNNING
SITUATION...WITH CLOUDS ALOFT. MODELS THEN SUGGEST AN INITIAL WEAK
WAVE ARRIVING BUY TUESDAY AFTERNOON...HOWEVER THE MUCH STRONGER
AND MORE ORGANIZED...NEGATIVELY TILTED WAVE APPEARS TO ARRIVE ON
TUESDAY NIGHT...PUSH NORTHEAST INTO MICHIGAN. WITH BEST DYNAMICS
ARRIVING ON TUESDAY AND WILL FOCUS MAIN PRECIP CHANCES ON TUESDAY
NIGHT...BUT MAY NEED TO INCLUDE SOME LOW CHANCES DURING THE
AFTERNOON ACROSS THE WESTERN PARTS OF THE STATE. GIVEN THE
OVERRUNNING SITUATION AND MAVMOS RUNNING TOO COOL...WILL TREND
HIGHS WARMER THAN MAVMOS TUESDAY AND LOW WARMER ON TUESDAY NIGHT
AS PRECIP WILL BE EXPECTED AS THE STRONGER SHORT WAVE PUSHES
NORTHEAST TO TOWARD MICHIGAN.
AFTER THIS SYSTEM DEPARTS ON TUESDAY NIGHT..ANOTHER BRIEF BREAK IS
EXPECTED ON WEDNESDAY DRY AIR WORKS INTO THE STATE FROM THE
SOUTHWEST. ALOFT ANOTHER DEEPER WAVE IS EXPECTED TO DIG OUT OF THE
PLAINS STATES AND PUSH TOWARD THE OHIO VALLEY FOR WEDNESDAY
NIGHT. WITH SUBSIDENCE IN PLACE AMID WARM AIR ADVECTION AND A DRY
FORECAST COLUMN WILL TREND TOWARD A PARTLY SUNNY WEDNESDAY AND
WILL TREND TEMPS WARMER THAN MAVMOS.
AS THE STRONG WAVE PUSHES ACROSS THE STATE ON WEDNESDAY NIGHT
ALONG WITH A STRONGER COLD FRONT...FAVORABLE CONDITIONS FOR PRECIP
APPEAR IN PLAY...INCLUDING A PERIOD OF WARMER AND MORE MOIST
SOUTHERLY FLOW AHEAD OF THE COLD FRONT. WILL TREND POPS HIGHER ON
WEDNESDAY NIGHT AND TREND LOWS WARMER GIVEN THE EXPECTED PRECIP
AND CLOUDS. THUNDER ON WEDNESDAY NIGHT LOOKS QUITE REASONABLE AS
FORECAST SOUNDINGS AT THIS TIME SHOW ATTAINABLE CONVECTIVE TEMPS
IN THE MIDDLE 50S...STEEP LAPSE RATES AND CAPES OVER 1000 J/KG.
GUESS SPRING IS HERE.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
ISSUED AT 321 AM EDT MON MAR 23 2015
A COLD FRONT WILL BE EXITING THE AREA BY THURSDAY MORNING BUT SOME
UPPER FORCING WILL LAG BEHIND IT...KEEPING CHANCES FOR RAIN IN THE
FORECAST FOR THURSDAY. BY THURSDAY NIGHT SURFACE HIGH PRESSURE
STARTS TO BUILD IN FROM THE NORTHWEST. HOWEVER CYCLONIC UPPER FLOW
WILL CONTINUE THROUGH FRIDAY UNTIL THE UPPER TROUGH AXIS MOVES
THROUGH THE AREA. THIS FEATURE WILL KEEP A SLIGHT CHANCE FOR
PRECIPITATION GOING FOR THURSDAY NIGHT AND FRIDAY. WITH COLD
ADVECTION TAKING PLACE AT ALL LEVELS WILL SEE SLIGHT CHANCE FOR RAIN
EARLY THURSDAY NIGHT CHANGE OVER TO A SLIGHT CHANCE FOR SNOW
LATE...AND A MIX WILL BE POSSIBLE INTO FRIDAY MORNING. ARCTIC HIGH
PRESSURE MOVING IN WILL BRING DECREASING CLOUD COVER AND MUCH COLDER
TEMPERATURES WITH HIGHS ON FRIDAY AND SATURDAY IN THE UPPER 30S TO
MID 40S AND LOWS FRIDAY NIGHT ONLY IN THE LOW TO MID 20S. SUNDAY THE
NEXT LOW PRESSURE SYSTEM WILL APPROACH AND BRING IN RAIN CHANCES
THROUGH SUNDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR 231200Z TAF ISSUANCE/...
ISSUED AT 643 AM EDT MON MAR 23 2015
PRECIPITATION AND LOWER CEILINGS WILL START TO MOVE INTO THE SITES
LATER TODAY FROM THE NORTHWEST. BASED ON UPSTREAM OBSERVATIONS AND
AVAILABLE GUIDANCE /ESPECIALLY THE HRRR/ THINK KLAF WILL MOST LIKELY
HAVE SNOW FOR A FEW HOURS...WITH A RAIN/SNOW MIX POSSIBLE AT KIND
AND RAIN FURTHER SOUTH. WILL TEMPO THESE IN AND USED HRRR FOR
TIMING...ARRIVING IN KLAF AFTER 16Z AND FINALLY IN KBMG AROUND 20Z.
THE SOUTHERN SITES MAY NOT SEE FLIGHT RESTRICTIONS WITH THESE
SHOWERS AND WILL KEEP THEM VFR FOR NOW. AT KIND THOUGH EXPECT MVFR
TO DEVELOP WITH THE PRECIP MOVING THROUGH AND AT KLAF COULD SEE IFR
WITH THE INCREASED LIKELIHOOD OF SNOW. WINDS WILL CONTINUE TO HAVE
AN EASTERLY COMPONENT /MAINLY ENE/ THROUGH THE DAY AND RUN AROUND
8-12 KTS. COULD SEE SOME GUSTS BUT NOT STRONG ENOUGH OR WIDESPREAD
ENOUGH TO INCLUDE AT THIS TIME.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
716 AM EDT MON MAR 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 510 AM EDT MON MAR 23 2015
QUIET WEATHER WILL CONTINUE THRU THE SHORT TERM. WATER VAPOR IMAGERY
AND RAP ANALYSIS SHOW A COUPLE OF SHORTWAVES MOVING THRU THE NW FLOW
OVER THE NRN PLAINS. ONE WAVE IS MOVING ACROSS IA/SRN MN WITH A
SECOND MORE WELL-DEFINED WAVE TO THE NW IN SRN MANITOBA. ALTHOUGH
THE NRN WAVE IS MORE DEFINED...THE SRN WAVE IS PRODUCING MORE
SIGNIFICANT PCPN DUE TO THE COMBINATION OF BETTER MOISTURE AND MUCH
STRONGER FGEN. NOTHING MORE THAN SOME HIGH CLOUDS HAVE SPREAD INTO
UPPER MI OVERNIGHT ON THE NRN EDGE OF THE SRN WAVE. WITH HIGH PRES
CENTERED JUST NE OF LAKE SUPERIOR DOMINATING THE UPPER LAKES...WINDS
HAVE BEEN LIGHT/CALM ACROSS THE FCST AREA DURING THE NIGHT. THIS HAS
ALLOWED TEMPS IN TRADITIONAL COLD SPOTS TO DROP OFF INTO THE SINGLE
DIGITS ABOVE ZERO OVER THE E WHERE CLOUDS HAVE BEEN THINNEST.
ALTHOUGH UPSTREAM SHORTWAVE IN SRN MANITOBA IS WELL-DEFINED NOW AND
HAS AN ASSOCIATED AREA OF SNOW...MODELS ARE IN EXCELLENT AGREEMENT
SHOWING THIS WAVE WEAKENING AND SHEARING SE IN THE CONFLUENT FLOW
BTWN DEPARTING TROF IN SE CANADA/NE CONUS AND BUILDING RIDGE MOVING
OUT OVER THE NRN PLAINS IN ADVANCE OF COMPLEX OF SHORTWAVE ENERGY
MOVING ACROSS THE PACIFIC NW/NRN ROCKIES. SO...WHILE CURRENT LOOK OF
THE WAVE BRINGS SOME CONCERN THAT -SN/FLURRIES COULD STILL REACH THE
FAR WRN FCST AREA THIS EVENING...WILL MAINTAIN A DRY FCST SINCE
MODELS ARE IN SUCH GOOD AGREEMENT ON THE PCPN DISSIPATING. THE DRY
FCST IS STRONGLY SUPPORTED BY THE VERY DRY ANTECEDANT AIR MASS OVER
THE AREA PER OBSERVED 00Z SOUNDINGS AT KINL/KGRB. THIS DRY AIR MASS
WILL BE EVEN MORE DIFFICULT TO OVERCOME SINCE THE WAVE WILL BE
WEAKENING.
MAINLY HIGH CLOUDS AFFECTING THE AREA TODAY WILL CLEAR OUT TONIGHT
AS FCST SOUNDINGS SHOW NOTABLE DRYING IN THE UPPER LEVELS AS
MID/UPPER LEVEL RIDGE APPROACHES. WITH HIGH PRES JUST E OF THE AREA
TODAY...LIGHT EASTERLY WINDS WILL TAKE ON A LAKE BREEZE COMPONENT TO
KEEP AREAS NEAR THE GREAT LAKES COOLER...THOUGH THIS COOLING WILL BE
MORE LIMITED NEAR THE WRN SHORE OF UPPER MI. EXPECT HIGH TEMPS TODAY
TO RANGE FROM THE UPPER 20S/AROUND 30F TO AROUND 40F. IT WILL BE
COOLEST OVER THE E...NEAR LAKE SUPERIOR FROM THE KEWEENAW EASTWARD
AND NEAR LAKE MICHIGAN...AND IT WILL BE WARMEST OVER THE FAR W WHERE
DOWNSLOPING WILL AID WARMING. LEANED TOWARD THE LOWER SIDE OF
GUIDANCE TONIGHT GIVEN EXPECTED CLEARING SKIES AND CONTINUED LIGHT
WINDS. THE COLDEST BIAS CORRECTED GUIDANCE HAS MINS BLO ZERO TONIGHT
AT SOME OF THE USUAL COLD SPOTS. THAT SEEMS TOO LOW GIVEN LIGHT
SOUTHERLY FLOW AND CONTINUED MODERATION OF AIR MASS. IF ANY
LOCATIONS DO FALL SUBZERO...IT WOULD OCCUR OVER THE FAR ERN FCST
AREA CLOSER TO DEPARTING HIGH PRES. IN GENERAL...EXPECT SOME SINGLE
DIGITS ABOVE ZERO IN THE INTERIOR CNTRL AND E. OTHERWISE...MINS WILL
BE IN THE TEENS WITH SOME LOWER 20S W.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 228 AM EDT MON MAR 23 2015
AFTERNOON HIGHS TUESDAY WILL BE ON AVERAGE 10F WARMER THAN TODAY.
THIS WILL BE THANKS TO THE WAA S WINDS AND 850MB TEMPS RISING TO 0
TO -3C BY LATE AFTERNOON AS THE SFC HIGH OVER FAR SE ONTARIO
CONTINUES TO EXIT THE PICTURE. THE TRADITIONAL DOWNSLOPE LOCATIONS
OVER THE W HALF NEAR LAKE SUPERIOR SHOULD BE ABLE TO CLIMB INTO THE
MID TO UPPER 40S. A FEW 50F READINGS WILL NOT BE OUT OF THE
QUESTION.
OUR EYES WILL BE ON THE SFC LOW OVER THE DAKOTAS TUESDAY...AND THE S
LOW SHIFTING FROM CENTRAL KS TO W IA/MO BY THE END OF THE DAY.
TAKING A LOOK AT 500MB THE S SHORTWAVE OVER THE CENTRAL PLAINS
TUESDAY MORNING WILL CONTINUE TO STRENGTHEN. UNLIKE WHAT WE HAVE
SEEN FROM SYSTEMS RECENTLY...THIS ONE HAS SOME GOOD MOISTURE TO WORK
WITH...STREAMING N FROM THE W GULF OF MEXICO. THE NEARLY STACKED
SYSTEM WILL SWING ACROSS WI/W LOWER MI BY DAYBREAK
WEDNESDAY...PUSHING MIXED PRECIP ALONG THE WI BORDER BY 06Z
WEDNESDAY. DRY SOUNDINGS BELOW 800MB INDICATE THAT IT MAY TAKE A BIT
FOR THE NEAR-SFC LAYER TO MOISTEN ENOUGH FOR PRECIP TO FALL. EXPECT
MAINLY SNOW IF THE GFS IS CORRECT. THE 18Z AND 00Z GFS RUNS...WITH
THE MOST E TRACK OF THE SFC LOW...KEEPS ENOUGH COLD ENOUGH AIR
OVERHEAD TO KEEP MOST OF THE PRECIP STAYING AS SNOW EVEN ALONG THE
WI BORDER AND OUT E /ONLY A BIT OF FZRN AROUND MNM WEDNESDAY
MORNING/. THE QPF IS ON THE ORDER OF 0.1-0.2 IN LESS ON THE LATEST
RUN. THE NAM CONTINUES TO GO HIGH ON THE FZRN POTENTIAL. WHILE THE
18Z RUN OF THE NAM WAS A BIT COLDER/THE 00Z RUN HAS THE SFC LOW JUST
SLIGHTLY DEEPER AND TO THE W. HOWEVER...THE QPF HAS BEEN VERY
JUMPY...WITH RUN TO RUN CONSISTENCY ISSUES. WILL NOT GO COMPLETELY
WITH THE NAM OR GFS SOLUTIONS. THE SOLUTIONS DIVERGE AS EARLY AS
TUESDAY AFTERNOON OVER E KS/W MO...WITH THE NAM/ECMWF ON THE SLOW
SIDE COMPARED TO THE GFS. IT WILL BE INTERESTING TO SEE HOW THE
SOLUTIONS PAN OUT OVER THE NEXT DAY OR SO. WILL KEEP THE MENTION OF
SNOW AND MIXED PRECIP IN THE HWO...WITH SOME SLIGHT ADJUSTMENT. WILL
CONTINUE WITH MODERATE TO LOWER CONFIDENCE WITH THIS PERIOD.
WHILE THE S SFC LOW SHIFTS ACROSS E UPPER MI/N LOWER MI WEDNESDAY
AFTERNOON THE LOW THAT WAS IN THE DAKOTAS WILL SLIDE ACROSS N MN. SO
EVEN THOUGH THE INITIAL LOW SHIFTS ACROSS E ONTARIO AND INTO S
QUEBEC THURSDAY EVENING..LOW PRESSURE WILL LINGER ACROSS UPPER MI
THROUGH THE NIGHT AS THE SECONDARY LOW SHIFTS IN.
THE DGZ FINALLY FALLS WELL INTO THE MOISTURE LAYER OVERNIGHT
WEDNESDAY NIGHT THROUGH EARLY FRIDAY MORNING AS THIS SECONDARY LOW
SINKS ACROSS N LOWER MI THURSDAY MORNING. ALTHOUGH 850MB TEMPS FROM
THURSDAY AFTERNOON ON WILL BE -16C OR COLDER OVER THE W HALF...WINDS
LOOK TO BE SHIFTING QUITE A BIT...ANYWHERE OUT OF THE NW TO N TO NE.
THIS WILL LIMIT THE DEVELOPMENT OF STRONG LES BANDS. STILL...LES
WILL BE POSSIBLE. AN ADDITIONAL 2-5IN OF NEW SNOW WILL BE POSSIBLE
OVER THE LONGER PERIOD OF WEDNESDAY NIGHT THROUGH EARLY
FRIDAY...WITH THE HIGHEST AMOUNTS OVER THE FAVORABLE N WIND
SNOWBELTS.
LOOK FOR DRY WEATHER TO TAKE HOLD AGAIN FRIDAY AFTERNOON...WHEN THE
LARGE SFC HIGH SET UP FROM CENTRAL CANADA THROUGH MUCH OF THE
CENTRAL PLAINS EDGES INTO THE UPPER GREAT LAKES. THIS RIDGE OF HIGH
PRESSURE WILL REMAIN ACROSS UPPER MI INTO EARLY SATURDAY...BEFORE
EXITING TO THE SSE. GIVEN A MOSTLY CLEAR SKY AND ASSUMING NO
LINGERING LES...SATURDAY MORNING COULD BE PRETTY CHILLY IN THE
TRADITIONAL COLD SPOTS OF INTERIOR UPPER MI. DID ADJUST VALUES DOWN
SLIGHTLY FROM THE OVERALL MODEL BLEND.
LOW PRESSURE OVER MUCH OF CENTRAL CANADA ON SATURDAY WILL SWING A
TROUGH ACROSS ONTARIO SATURDAY NIGHT THROUGH SUNDAY. WHILE THE GFS
IS MORE PROGRESSIVE WITH THIS SYSTEM...THE ECMWF DEEPENS AN OFFSHOOT
OF THE MAIN LOW OVER ONTARIO AVERAGING 985MB. AT THIS POINT BOTH THE
ECMWF AND GFS PIN POINT THE E HALF OF UPPER MI TO GET 0.25IN OR MORE
OF LIQUID LATE SATURDAY NIGHT/EARLY SUNDAY MORNING. WITH 850MB TEMPS
OF -3 TO -5C A HEAVY WET SNOW IS MOST LIKELY. WILL HOLD OFF ON ANY
MENTION IN THE HWO QUITE YET...AS SEVERAL CHANGES WILL BE POSSIBLE
BETWEEN NOW AND THEN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 716 AM EDT MON MAR 23 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
DRIFTING S THRU ONTARIO WILL ALLOW VFR CONDITIONS TO CONTINUE AT
KIWD/KCMX/KSAW THRU THIS FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 510 AM EDT MON MAR 23 2015
HIGH PRES JUST NE OF LAKE SUPERIOR WILL DRIFT SOUTHEAST...REACHING
SOUTHERN ONTARIO BY TUE MORNING AND THE MID ATLANTIC STATES TUE
AFTN. WITH PRES GRADIENT REMAINING WEAK...WINDS WILL BE BLO 20KT
ACROSS LAKE SUPERIOR. A LOW PRESSURE SYSTEM OVER THE CENTRAL PLAINS
TUE WILL TRACK NE...CROSSING FAR NRN LWR MI WED AFTN. WINDS SHOULD
NOT STRENGTHEN MUCH AHEAD OF THIS FEATURE AS PRES GRADIENT DOES NOT
TIGHTEN SIGNIFICANTLY. STRONGEST WINDS WILL OCCUR THU AS HIGH PRES
BUILDS S TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO
THE UPPER LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...
AND IT`S NOT OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR
FOR A TIME. WINDS WILL THEN DIMINISH FRI AS A HIGH PRESSURE RIDGE
MOVES OVER THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1000 AM CDT MON MAR 23 2015
.UPDATE...LATEST MODELS INDICATE CLEARING OVER THE SOUTHEAST HALF OF
THE REGION TODAY MAY BE A BIT SLOWER THAN PREVIOUSLY
ANTICIPATED...WITH POTENTIAL THAT SOME OF THE LOW CLOUDS IN PORTIONS
OF EAST/SE MS MAY HANG ON THROUGH THE AFTERNOON. MOST OF THE DRIZZLE
IS DONE...BUT HRRR SUGGESTS AT LEAST SOME ISOLATED SPRINKLES
UNDERNEATH THE MOST DOGGED CLOUDS CANNOT BE RULED OUT THROUGH THE
DAY AND THE FORECAST WAS UPDATED TO REFLECT THIS. CONSIDERING THE
MORE PERSISTENT CLOUDS THE HIGH TEMP FORECAST FOR THIS AFTERNOON IN
THE SOUTHEAST HALF OF THE CWA WAS LOWERED BY 2 TO 3 DEGREES IN MOST
CASES. /BB/
&&
.PREV DISCUSSION... /ISSUED 435 AM CDT MON MAR 23 2015/
DISCUSSION...TODAY THROUGH TUESDAY NIGHT...
A WEAK TROWAL ASSOCIATED WITH CYCLONIC FLOW ON THE BACK SIDE OF THE
DEPARTING LOW PRESSURE SYSTEM IS RESULTING IN CONTINUED -DZ/RA EARLY
THIS MORNING WITH MEASURABLE PRECIP STILL BEING REPORTED AT
JAN/HKS...BUT GUIDANCE INDICATES THIS SYSTEM WILL BE PROGRESSIVE...
AND EXPECT DRIZZLE TO END BY MID MORNING OVER ERN MS. WEAK LOW LEVEL
COLD ADVECTION WILL SUPPORT STRATUS DEVELOPMENT THROUGH THE MORNING
AND PERHAPS INTO THE AFTERNOON OVER CENTRAL/ERN MS...BUT WITH
SURFACE HIGH PRESSURE BUILDING OVER THE ARKLAMISS SKIES SHOULD CLEAR
AT MOST PLACES AS WE GO THROUGH LATE AFTERNOON AND INTO THE EVENING.
DEPENDING ON HOW MUCH INSOLATION/EVAPORATION TAKE PLACE TODAY...
CLEARING COULD SET THE STAGE FOR CONSIDERABLE FOG DEVELOPMENT AS LOW
TEMPERATURES POSSIBLY EXCEED CROSS-OVER TEMPS BY SEVERAL DEGREES.
LOW STRATUS/FOG COULD LINGER WELL INTO TUESDAY MORNING BEFORE MIXING
OUT BY AFTERNOON IN A DEVELOPING WARM ADVECTION PATTERN. CONTINUED
LOW LEVEL WARM ADVECTION MAY BRING MORE STRATUS/FOG POTENTIAL
TUESDAY NIGHT. /EC/
LONG TERM...WEDNESDAY THROUGH SUNDAY - GULF MOISTURE WILL BE SLOW TO
RETURN AHEAD OF AN APPROACHING STRONG COLD FRONT MOVING THROUGH THE
OZARKS BY WEDNESDAY EVENING. THERE WILL BE JUST ENOUGH WEAK MOISTURE
TRANSPORT TO PRODUCE SOME LIGHT SHOWERS ACROSS THE SOUTH DURING
WEDNESDAY AFTERNOON. FOR LATE WEDNESDAY NIGHT THERE WILL BE ENOUGH
MOISTURE CONVERGENCE AND INSTABILITY TO PRODUCE SOME CONVECTION
AHEAD OF THE COLD FRONT. THE STRONG COLD FRONT WITH THE ASSOCIATED
CONVECTION WILL PUSH ACROSS THE REGION ON THURSDAY. THIS WILL BE
ASSOCIATED WITH AN UNSEASONABLE UPPER TROUGH AND COOL PATTERN FOR
THURSDAY NIGHT THROUGH THE REST OF THE WEEK. THIS WAS AGREED UPON BY
THE CANADIAN...EURO/PARALLEL EURO...AND GFS OPERATIONAL MODELS AND
THEIR ENSEMBLES. HEIGHTS AND LOW LEVEL TEMPS WILL BE AROUND 3
STANDARD DEVIATIONS BELOW NORMAL. FOR THURSDAY EVENING THERE WILL BE
SOME POST FRONTAL SHOWERS ACROSS THE CWA WHICH WILL END BY FRIDAY.
OUR COOL PATTERN WILL BEGIN IN THE WAKE OF THE FRONT FOR THURSDAY
NIGHT WITH NEAR SEASONAL READINGS IN THE 40S. THE SHOWERS WILL END
BY FRIDAY WITH HIGHS IN THE 50S AND 60S...WHICH WILL BE 5 TO 15
DEGREES BELOW NORMAL. A STRONG UPPER TROUGH IN THE WAKE OF THE FRONT
WILL PUSH ACROSS THE ARKLAMISS ON FRIDAY INTO FRIDAY NIGHT. LOWS
WILL DIP INTO THE 30S AND 40S FOR FRIDAY NIGHT. IT WILL BE EVEN
COOLER SATURDAY WITH HIGHS JUST IN THE 50S. FOR SATURDAY NIGHT WE
WILL BE IN A GOOD SET UP FOR SOME STRONG RADIATIONAL COOLING AS
SURFACE HIGH PRESSURE SETTLES INTO THE REGION BEHIND THE DEPARTING
STRONG UPPER TROUGH. THERE COULD BE A RISK FOR SOME FREEZING TEMPS
IN THE LOWER 30S IN SOME AREAS. FOR NOW WILL KEEP LOWS ABOVE
FREEZING FOR SATURDAY NIGHT. SOME OF THE LOWER END OF THE ENSEMBLE
GUIDANCE KEEPS LOWS AROUND THE UPPER 20S TO FREEZING. RESIDENTS ARE
URGE TO KEEP UPDATED ON THE POTENTIAL COLDER TEMPS IN REGARDS TO
TENDER VEGETATION. THE CIPS MODELS JUST TO GIVEN AN IDEA OF THE
POTENTIAL...SLU CIPS ANALOG GUIDANCE CENTERED ON SATURDAY INDICATES
60-70% EXCEEDANCE OF THE <32F FOR 5 HR THRESHOLD OVER EAST CENTRAL
MS...AND > 50% EXCEEDANCE OF THE <32F FOR 1 HR THRESHOLD FOR MOST OF
THE FORECAST AREA. FOR NOW THIS FAR OUT WILL NOT MENTION THE
POTENTIAL IN THE HWO...BUT WILL MONITOR FOR LATER FORECAST
PACKAGES./17/
&&
.AVIATION...SKIES HAVE BEGUN CLEARING ACROSS THE NORTH THIS
MORNING...KGLH...KGWO...AND KGTR...WITH VFR FLIGHT CATEGORIES
PREVAILING AT THOSE SITES. SKIES WILL BE A BIT SLOWER TO CLEAR AT
REMAINING TAF LOCALES...THUS RESULTING IN MAINLY MVFR FLIGHT
CATEGORIES UNTIL CLEARING OCCURS LATER THIS AFTERNOON. OTHERWISE...
WINDS WILL BE NORTHERLY BETWEEN 7-10 KNOTS TODAY. WINDS WILL BECOME
MORE EASTERLY OVERNIGHT AND SUBSIDE TO BETWEEN 3-5 KNOTS INTO EARLY
TUESDAY MORNING. A BOUT OF MVFR/IFR VISIBILITIES CAN`T BE RULED OUT
AROUND SUNRISE TUESDAY MORNING AS A RESULT OF PATCHY FOG. ANY FOG
THAT DEVELOPS SHOULD DISSIPATE BY 15Z TUESDAY. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 67 50 76 55 / 11 0 0 4
MERIDIAN 67 48 74 52 / 14 0 0 4
VICKSBURG 69 49 76 54 / 5 0 0 4
HATTIESBURG 68 51 76 57 / 14 0 0 7
NATCHEZ 67 51 75 55 / 8 0 0 5
GREENVILLE 70 49 73 55 / 2 0 0 4
GREENWOOD 72 50 75 56 / 3 0 0 4
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
BB/19/EC
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
858 AM MDT MON MAR 23 2015
.UPDATE...
ONLY UPDATE TO THE GOING FORECAST WAS TO TAPER DOWN CLOUD COVER
FOR THE NEXT SEVERAL HOURS TO MATCH CURRENT OBSERVATIONS. HIGH
TEMPERATURES TODAY WERE GOING TO BE TRICKY DUE TO CLOUD COVER AND
THE APPROACH OF AFTERNOON CONVECTION FROM THE WEST. SINGER
&&
.SHORT TERM...VALID FOR TDY AND TUE...
A RELATIVELY ACTIVE PERIOD WITH SHOWER CHANCES IS IN STORE DURING
THE NEXT TWO DAYS...WITH THE GREATEST CHANCE OF MOISTURE FOR MOST
AREAS COMING LATE THIS AFTERNOON THROUGH TONIGHT. AREA MOUNTAINS
WILL GET SEVERAL INCHES OF SNOW IN THIS PATTERN AS WELL.
FIRST OF ALL...WE HAVE PATCHY FOG IN THE FORECAST THROUGH THE MID
MORNING IN THE EKALAKA AND BAKER AREAS...WHERE VISIBILITY IS DOWN
TO 1/4SM AS OF 09 UTC. HRRR SIMULATIONS SUGGEST THE FOG SHOULD BE
DISSIPATING BY AROUND 15 UTC.
TODAY...A MILD DAY IS IN STORE WITH HIGHS MAINLY IN THE 60S F OUT
AHEAD OF THE APPROACHING 500-MB TROUGH. THE SPEED AT WHICH CLOUDS
THICKEN COULD PRODUCE SOME ERROR IN FORECAST HIGHS THOUGH. SHOWERS
WILL LIKELY BEGIN TO DEVELOP AND/OR MOVE INTO WESTERN PORTIONS OF
SOUTH CENTRAL MT THIS AFTERNOON AS HEIGHT FALLS COMMENCE AND LEAD
TO INCREASING QG-FORCING ALOFT. WE RELIED ON THE 00 UTC MODELS AND
MORE CONTEMPORARY HIGH-RESOLUTION AND CONVECTION-ALLOWING GUIDANCE
LIKE THE RAP AND HRRR TO HOLD OFF THE CHANCE OF SHOWERS WITHIN THE
FORECAST FOR BILLINGS EASTWARD ACROSS SOUTHEASTERN MT UNTIL 21 UTC
/3 PM MDT/. SPEAKING OF SOUTHEASTERN MT...POPS THIS AFTERNOON OVER
THAT PART OF THE STATE ARE CONDITIONAL ON WEAK INSTABILITY FORMING
AND CONTRIBUTING TO CONVECTIVE ELEMENTS DEEPENING ENOUGH TO YIELD
PRECIPITATION. THAT/S FAR FROM CLEAR...THOUGH THE FAVORED NON-NAM
SET OF 00 UTC GUIDANCE LIKE THE GFS DOES SUPPORT SOME 100-200 J/KG
OF MUCAPE THERE /AND BACK FURTHER WEST AROUND LIVINGSTON/ DUE TO A
PLUME OF STEEP MID-LEVEL LAPSE RATES EXCEEDING 8 C/KM...SO WE DID
LEAVE A SLIGHT CHANCE OF THUNDERSTORMS IN WITH THE SHOWERS IN BOTH
OF THOSE AREAS THIS AFTERNOON. WE LEFT THEM IN SOUTHEASTERN MT FOR
THE EARLY EVENING FOR SIMILAR REASONS.
TONIGHT...A RATHER STRONG...BUT QUICK-MOVING BATCH OF FORCING WILL
CROSS THE AREA AND LIKELY YIELD AN EASTWARD-MOVING ROUND OF SHOWER
ACTIVITY. WE HAVE THE HIGHEST /LIKELY-RANGE/ POPS IN PLACE ACROSS
SOUTHEASTERN MT WHERE THAT FORCING WITH THE 500-MB TROUGH LOOKS TO
INTERCEPT A NARROW RIBBON OF HIGHER MOISTURE THAT THE 00 UTC MODEL
GUIDANCE FORECASTS TO MOVE NORTHWARD ALONG THE HIGH PLAINS WITH AN
AXIS OF PRECIPITABLE WATER VALUES OF 0.50 INCHES MOVING OUT OF THE
SOUTHERN PLAINS AND INTO EASTERN MT OVERNIGHT. THE DODGE CITY...KS
OBSERVED SOUNDING FROM 00 UTC MARCH 23RD DID SAMPLE A PRECIPITABLE
WATER VALUE OF 0.42 INCHES...WHICH SUGGESTS THE GUIDANCE DOES HAVE
A HANDLE ON THIS SCENARIO. MOISTURE TOTALS WITH THE HIGHEST CHANCE
OF SOME QUARTER INCH RAIN TOTALS WILL THUS ALSO BE IN SOUTHEASTERN
MT. MEANWHILE...TIME-LAGGED AND ONE-RUN ENSEMBLE GUIDANCE BACK TO
THE WEST IN BILLINGS CONTINUES TO SUGGEST THE CITY WILL LIKELY GET
0.05 INCHES OR LESS OF MOISTURE OUT OF THIS SYSTEM.
TUESDAY INTO TUESDAY NIGHT...COOLER AND UNSETTLED WEATHER WILL BE
THE THEME BEHIND TONIGHT/S WAVE PASSAGE. NOTE THAT THE 00 UTC GEM
AND ECMWF ACTUALLY SUGGEST MORE BONAFIDE WRAP-AROUND MOISTURE AND
POSSIBLY EVEN SNOW IN BAKER EARLY TUESDAY MORNING AS THEY PLACE A
GREATER EMPHASIS ON THE NORTHERN PIECE OF THE TROUGH ALOFT. WE DO
NEED TO KEEP AN EYE ON THAT...BUT CONFIDENCE IN HOW THAT WILL END
UP PLAYING OUT IS LOW. OTHERWISE...THERE IS GREATER CONFIDENCE IN
ANOTHER WEAKER SHORTWAVE TROUGH DROPPING ACROSS SOUTH CENTRAL MT
TUESDAY AFTERNOON AND EVENING WITH CONVECTIVELY-AIDED SHOWERS OF
RAIN AND EVENTUALLY SNOW SHOWERS BY TUESDAY NIGHT. THIS SITUATION
IS ONE THAT CAN YIELD ACCUMULATING SNOW IN THE FOOTHILLS LIKE AT
RED LODGE...AND IF GUIDANCE REMAINS CONSISTENT IN ITS SIMULATION
OF THIS SCENARIO THEN WE MAY NEED TO INCREASE SNOW AMOUNTS WITH A
LATER FORECAST RELEASE IN THE FOOTHILLS. SCHULTZ
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
COOLER AND UNSETTLED NORTHERLY FLOW WILL REMAIN OVER THE REGION
THROUGH THURSDAY. LAPSE RATES WILL BE STEEPEST ON WEDNESDAY WITH
SOME DIURNAL RAIN/SNOW SHOWERS ANTICIPATED...ESPECIALLY IN NW FLOW
FAVORED AREAS...BUT W/OUT MUCH SYNOPTIC FORCING. A SURGE OF
MOISTURE SPILLING OVER THE WESTERN CONUS RIDGE WILL KEEP THE
POTENTIAL FOR SHOWER ACTIVITY GOING WEDNESDAY NIGHT AND THURSDAY.
LATEST MODEL TRENDS SUGGEST BACKDOORING COOLING WHICH WILL
INCREASE THE LOW LEVEL BAROCLINICITY IN OUR CWA...THOUGH MODELS
ARE DIFFERENT IN WHERE THEY PAINT HIGHEST QPF. IF SFC TEMPS REMAIN
COOL ENOUGH WE COULD SEE SOME WET SNOWFALL IN A COMBINATION OF OUR
N-NW FLOW UPSLOPE AREAS AND ALONG SFC BOUNDARY. HAVE RAISED POPS
IN OUR SOUTH CENTRAL PARTS THURSDAY INTO THURSDAY NIGHT...AND HAVE
LOWERED TEMPS A BIT IN OUR CENTRAL AND EAST. OF COURSE THE NW FLOW
ALOFT WILL FAVOR THE BIGHORN MTNS FOR SNOWFALL THRU THE PERIOD.
STRONG RIDGE ALONG THE PAC COAST WILL BEGIN TO SHIFT EAST ON
FRIDAY BRINGING US RAPID DOWNSLOPE WARMING AS HEIGHTS SURGE INTO
THE 570S ACROSS WESTERN AND CENTRAL MT. SHOULD SEE HIGH TEMPS BACK
NEAR 70F IN OUR WEST BUT PROXIMITY TO SLOWER DEPARTING SFC HIGH IN
THE PLAINS SHOULD KEEP OUR EAST COOLER...ESPECIALLY AFTER A COLD
MORNING. HAVE ADJUSTED TEMPS IN OUR EAST DOWN SOME PER MODEL
CONSENSUS.
IT APPEARS SATURDAY WILL BE THE WARMEST DAY OF THE EXTENDED PERIOD
AS THE RIDGE AXIS SHIFTS FURTHER EAST AND BEGINS TO FLATTEN IN
RESPONSE TO NEXT SHORTWAVE OFF THE PACIFIC. MODELS HAVE TRENDED
SLOWER WITH A COLD FRONTAL PASSAGE...IT NOW LOOKS TO OCCUR
SATURDAY NIGHT...AND THIS WILL SET THE STAGE FOR A DRY/WINDY AND
VERY WARM SATURDAY. GIVEN SUCH ANOMALOUSLY HIGH HEIGHTS AND THE
STRONG DOWNSLOPE PREFRONTAL FLOW HAVE RAISED EXPECTED HIGHS
FURTHER INTO THE 70S.
MODEST COOL DOWN IN STORE FOR SUNDAY BEHIND THE CLIPPER SYSTEM...
WHICH MAY BRING A LITTLE SHOWER ACTIVITY SATURDAY NIGHT INTO
SUNDAY. IT IS LOOKING MORE AND MORE LIKE MARCH WILL END ON A WARM
NOTE WITH UPPER RIDGING EXPECTED TO PERSIST THRU EARLY NEXT WEEK.
JKL
&&
.AVIATION...
EXPECTING CLEAR SKIES THIS MORNING BEFORE THE CLOUDS START FILLING
IN AHEAD OF AN UPPER LEVEL DISTURBANCE. THE POTENTIAL FOR SOME
CONVECTION EXISTS MAINLY NEAR KLVM BY THIS AFTERNOON. RAIN SHOWERS
WILL FILL IN NEAR KBIL BY LATE THIS AFTERNOON...AND KMLS AND KBHK
BY THIS EVENING. THE SHOWER ACTIVITY WILL COINCIDE WITH A PACIFIC
COLD FRONT MOVING INTO THE AREA FROM THE WEST. MVFR CONDITIONS
WILL BE POSSIBLE WITH PRECIP ACTIVITY AND MOUNTAIN OBSCURATIONS
ARE POSSIBLE DUE TO SNOW SHOWER ACTIVITY AT HIGHER ELEVATIONS.
SINGER
&&
.PRELIMINARY POINT TEMP/POPS...
TDY TUE WED THU FRI SAT SUN
-------------------------------------------------------
BIL 064 039/055 031/048 034/051 032/070 046/077 042/061
2/W 54/W 43/W 32/W 10/B 01/N 22/W
LVM 058 031/048 028/048 034/055 035/070 047/072 041/061
6/T 55/W 53/W 22/W 10/N 01/N 22/W
HDN 068 037/058 029/048 032/051 028/070 039/079 038/063
2/W 53/W 33/W 32/W 10/B 01/N 22/W
MLS 068 039/055 027/045 026/048 026/066 039/076 036/060
2/T 62/W 12/W 22/W 10/B 01/N 21/B
4BQ 070 037/056 027/045 026/047 026/064 038/078 037/060
3/T 63/W 12/W 23/W 10/B 01/N 21/B
BHK 064 036/051 024/039 020/041 021/058 035/074 033/055
1/B 74/W 12/J 22/J 10/B 01/N 21/B
SHR 066 035/053 027/045 028/048 026/065 038/078 039/060
2/W 54/W 44/W 43/W 20/B 00/B 22/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
917 AM EDT MON MAR 23 2015
.SYNOPSIS...
A SERIES OF WEAK AREAS OF LOW PRESSURE WILL MOVE EAST ALONG A
STALLED FRONT SOUTH OF THE AREA THROUGH TUESDAY. HIGH PRESSURE
WILL EXTEND INTO THE AREA FROM THE NORTH THROUGH MIDWEEK. A STRONG
COLD FRONT WILL APPROACH FROM THE WEST THURSDAY AND MOVE THROUGH
FRIDAY. LOW PRESSURE WILL MOVE ACROSS SOUTHEAST OF THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 915 AM MONDAY...REMOVED POPS NRN TIER AND LOWERED SRN TIER
AS TRENDS CONT TO SHOW PRECIP DIMINISHING. PLENTY OF CLOUDS WILL
CONT WITH COOL HIGHS IN UPR 40S NE TO MID/UPR 50S SW. GUSTY NE
WINDS EXPECTED ALONG THE BEACHES.
PREV DISC...BULK OF THE PRECIPITATION NOW OFFSHORE WITH JUST SOME
LIGHT RAIN SKIRTING THE IMMEDIATE COAST. SURFACE OBSERVATION
INDICATE THE LIGHT RETURNS INLAND STILL NOT REACHING THE GROUND.
PER THE LATEST RUN OF THE 3KM HRRR MODEL...HAVE SCALED POPS BACK
TO CHANCE...WITH 40 PCT ALONG THE SOUTHERN COAST TAPERING BACK TO
SLIGHT CHANCE OVER THE FAR NORTHWESTERN COUNTIES. ADDITIONAL
SHORTWAVE ENERGY COULD PRODUCE A FEW LIGHT SHOWERS THROUGH
MIDDAY...BUT GUIDANCE ALL SHOWS DRIER AIR FILTERING IN AFTER NOON
WITH DEWPOINTS DROPING BACK INTO THE 30S. IT WILL BE A CHILLY
START TO THE WORKWEEK WITH HIGHS TEMPERATURES LINGERING IN THE
UPPER 40S OVER THE NORTHERN OUTER BANKS WITH LOW/MID 50S
ELSEWHERE...EXCEPT A FEW UPPER 50S OVER THE FAR SOUTHWESTERN
COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 330 AM MONDAY...LOW PRESSURE WILL MOVE WELL EAST OF THE AREA
TONIGHT AS COOL HIGH PRESSURE BUILDS SOUTH FROM CANADA. EXPECT A
VEIL OF MID CLOUDS TO HANG AROUND...BUT TEMPERATURES WILL STILL BE
CHILLY FOR LATE MARCH WITH LOWS RANGING IN THE MID/UPPER 30S
INLAND TO THE LOWER 40S OUTER BANKS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 330 AM MON...LONG TERM PERIOD WILL FEATURE VERY
CHANGEABLE WEATHER PATTERN TYPICAL OF EARLY SPRING WITH LARGE
VARIATION IN TEMPERATURES AND AN UNSETTLED PATTERN.
MAINLY DRY CONDITIONS TUE NIGHT INTO WED WITH HIGH PRES TO THE
NORTHEAST REESTABLISHING ITSELF ACROSS E NC WITH ZONAL FLOW ALOFT.
SOME MODERATION IN TEMPS FOR TUE THOUGH STILL BELOW CLIMO WITH HIGHS
NEAR 50 NORTHEAST TO NEAR 60 SOUTHWEST UNDER PARTLY SUNNY SKIES.
LOWS NEAR CLIMO TUE NIGHT WITH READINGS IN THE 40S. CONTINUED
PREVIOUS FCST TREND WITH PCPN HOLDING OFF DURING THE DAY WED AS
RETURN FLOW BECOMES SOUTHEAST LATE IN THE DAY THOUGH LOW LEVELS
STILL DRY WITH JUST AN INC IN CLOUD COVER EXPECTED. HIGHS EXPECTED
NEAR 70 AWAY FROM THE COAST WITH 50S ON THE OUTER BANKS WITH
CONTINUED NORTHEAST BREEZE KEEPING IT COOLER HERE.
INC CHANCES FOR RAIN SHOWERS WED NIGHT AS RETURN SSW FLOW
STRENGTHENS AND RAPID INC IN LOW LEVEL MOISTURE ENSUES. SHORTWAVE
ENERGY PIVOTING AROUND LONG WAVE CENTRAL CONUS TROUGH WILL AID IN
UPR SUPPORT FOR SCT TO NUMEROUS RAIN SHOWERS.
FOR THUR...WARM AND HUMID DAY EXPECTED WITH BUILDING LOW LEVEL
THICKNESSES AND RESPONDING INC TEMPS AND DEWPOINTS EXPECTED AHEAD OF
APPROACHING STRONG COLD FRONT AND AFOREMENTIONED LONG WAVE TROUGH.
SFC INSTABILITY WILL BE PRESENT WITH PARTLY SUNNY SKIES EXPECTED
ALONG WITH SUFFICIENT DEEP LAYER SHEAR FOR THE POSSIBILITY OF
ORGANIZED THUNDER. HOWEVER...UPR SUPPORT WILL REMAIN WELL WEST OF
THE AREA AS POSTITVELY TILTED TROUGH IS SLOW TO MAKE HEADWAY TOWARDS
E NC...SO THREAT FOR SEVERE IS MARGINAL AT THIS TIME. HIGHS WILL
EASILY CLIMB INTO THE 70S...POSSIBLY HIGHER IF MORE SUNSHINE BREAKS
OUT. PRECIP THREAT WILL CONTINUE INTO THUR NIGHT AS 23/00Z
GFS/ECM/CMC IN GENERAL AGREEMENT ON A THUR NIGHT/FRI MORNING FRONTAL
PASSAGE.
FOR FRIDAY...POSITIVELY TILTED UPR TROUGH REMAINS WEST OF THE AREA
DESPITE THE SFC FRONTAL PASSAGE. MODELS INDICATE MORE SHORTWAVE
ENERGY ALOFT PRODUCING CHANCES FOR PRECIP THROUGH THE DAY AND WILL
RETAIN THE CHANCE POPS. TEMPS WILL BE NEAR CLIMO WITH HIGHS
GENERALLY IN THE 60S...WITH COOLER 50S OBX UNDER NORTHEAST SFC FLOW.
FRI NIGHT THROUGH SAT THERE IS DISAGREEMENT WITH RESPECT TO UPR
SUPPORT AS TROUGH AXIS WORKS THROUGH E NC. DETERMINISTIC GFS/CMC
CONTINUE WITH A WETTER SOLN WITH A COLD RAIN POSSIBLY MIXING WITH A
FEW SNOW SHOWERS...THOUGH LATEST 23/00Z ECMWF HAS A DRIER TREND.
WILL CONTINUE PREVIOUS CHANCE POPS AS WOULD LIKE TO SEE MORE
CONSISTENCY FROM ECMWF BEFORE MAKING LARGE SCALE CHANGES.
SUNDAY WILL BE QUITE COLD FOR LATE MARCH WITH TEMPS SOME 15-20
DEGREES BELOW CLIMO AND POSSIBLE FROST OR FREEZING CONDITIONS FOR E
NC. GROWING SEASON WILL BEGIN ACROSS ALL OF EASTERN NC ON MARCH 28.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 12Z TUESDAY/...A GENERALLY DRY SUB CLOUD LAYER
HAS PREVENTED CEILINGS FROM DROPPING DESPITE SOME LIGHT
PRECIPITATION RETURNS ON RADAR. THE BULK OF THE LIGHT RAIN HAS
OCCURRED ALONG THE SOUTHERN COAST. CEILINGS ARE CURRENTLY MVFR AT
KISO...BUT ANTICIPATE ALL CEILINGS TO BE VFR BY 15Z OR SO AS
DEWPOINTS DROP INTO THE 30S. EXPECT VFR CONDITIONS OVERNIGHT AS
DRY COOL HIGH PRESSURE SETTLES SOUTH.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...VFR CONDITIONS WILL DOMINATE TUE AND WED. NEXT
CHANCE FOR RAIN SHOWERS AND SUB VFR CONDITIONS WILL BE WED NIGHT
INTO THUR AS MOISTURE STREAMS NORTHWARD AHEAD OF STRONG COLD FRONT
SET TO PASS THROUGH BY FRIDAY MORNING. S TO SW WINDS WILL BE GUSTY
ON THURSDAY.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 915 AM MONDAY...INCREASED WINDS A BIT CST PER LATEST OBS AND
MDLS AND EXTENDED SCA FOR SOME ZONES INTO THIS EVENING.
PREV DISC...WINDS HAVE STARTED TO INCREASE ON THE SOUNDS AND
NORTHERN WATERS OVER THE PAST COUPLE OF HOURS. THE GRADIENT WILL
INCREASE DRAMATICALLY OVER THE NEXT FEW HOURS BETWEEN LOW PRESSURE
PASSING TO OUR SOUTH AND CANADIAN HIGH PRESSURE BUILDING DOWN FROM
THE NORTH. EXPECT NORTHEAST WINDS TO INCREASE TO 20 TO 25 KNOTS
OVER THE COASTAL WATERS WITH A PERIOD OF 25 TO 30 KNOT WINDS
POSSIBLE OVER PORTIONS OF THE CENTRAL WATERS THROUGH THE MID TO
LATE MORNING HOURS. ON THE SOUNDS...WINDS WILL GENERALLY BE 15 TO
25 KNOTS WITH A FEW GUSTS TO 30 KNOTS POSSIBLE THIS MORNING
ESPECIALLY. PER LATEST LOCAL NWPS/SWAN MODEL...SEAS WILL BUILD TO
AS HIGH AS 7 OR 8 FEET THROUGH THE LATE MORNING AND AFTERNOON
HOURS...ESPECIALLY CENTRAL AND NORTHERN WATERS. ONLY CHANGE TO
ADVISORIES WAS TO EXTEND FAR SOUTHERN WATERS INTO TUESDAY EVENING
WITH SEAS REMAINING ELEVATED.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...THE PRESSURE GRADIENT LOOSENS ON TUE
WITH SCA CONDITIONS ENDING. HIGH PRESSURE WILL CONTINUE TO PRODUCE
NORTHEAST WINDS IN THE 15-20 KT RANGE THROUGH TUE NIGHT. THE HIGH
WILL MOVE OFF THE COAST ON WEDNESDAY AND WINDS WILL VEER TO
SOUTHEAST LATE IN THE AFTERNOON. THE FLOW WILL CONTINUE TO VEER TO
SOUTH WEDNESDAY NIGHT AND THURSDAY AS THE HIGH MOVES EAST AND A COLD
FRONT APPROACHES FROM THE WEST. SCA CONDITIONS WILL LIKELY REDEVELOP
BY LATE WED NIGHT OR THURSDAY AS SOUTHERLY WINDS STRENGTHEN AND SEAS
BUILD ABOVE 6 FT. FRONT WILL PASS OFF THE COAST FRI MORNING WITH
WINDS TURNING NORTHERLY. THE NORTH WINDS WILL STRENGTHEN ON SATURDAY
AS STRONG COLD AIR ADVECTION MOVES INTO THE E NC WATERS WITH GUSTY
NORTH WINDS AND HIGH SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR AMZ130-
131.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...RF/CTC
SHORT TERM...CTC
LONG TERM...TL
AVIATION...CTC/TL
MARINE...RF/CTC/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
652 AM EDT MON MAR 23 2015
.SYNOPSIS...
A SERIES OF WEAK AREAS OF LOW PRESSURE WILL MOVE EAST ALONG A STALLED
FRONT SOUTH OF THE AREA THROUGH TUESDAY. HIGH PRESSURE WILL EXTEND
INTO THE AREA FROM THE NORTH THROUGH MIDWEEK. A STRONG COLD FRONT
WILL APPROACH FROM THE WEST THURSDAY AND MOVE THROUGH FRIDAY.
LOW PRESSURE WILL MOVE ACROSS SOUTHEAST OF THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 650 AM MONDAY...BULK OF THE PRECIPITATION NOW OFFSHORE WITH
JUST SOME LIGHT RAIN SKIRTING THE IMMEDIATE COAST. SURFACE
OBSERVATION INDICATE THE LIGHT RETURNS INLAND STILL NOT REACHING
THE GROUND. PER THE LATEST RUN OF THE 3KM HRRR MODEL...HAVE SCALED
POPS BACK TO CHANCE...WITH 40 PCT ALONG THE SOUTHERN COAST
TAPERING BACK TO SLIGHT CHANCE OVER THE FAR NORTHWESTERN COUNTIES.
ADDITIONAL SHORTWAVE ENERGY COULD PRODUCE A FEW LIGHT SHOWERS
THROUGH MIDDAY...BUT GUIDANCE ALL SHOWS DRIER AIR FILTERING IN
AFTER NOON WITH DEWPOINTS DROPING BACK INTO THE 30S. IT WILL BE
A CHILLY START TO THE WORKWEEK WITH HIGHS TEMPERATURES LINGERING
IN THE UPPER 40S OVER THE NORTHERN OUTER BANKS WITH LOW/MID 50S
ELSEWHERE...EXCEPT A FEW UPPER 50S OVER THE FAR SOUTHWESTERN
COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 330 AM MONDAY...LOW PRESSURE WILL MOVE WELL EAST OF THE AREA
TONIGHT AS COOL HIGH PRESSURE BUILDS SOUTH FROM CANADA. EXPECT A
VEIL OF MID CLOUDS TO HANG AROUND...BUT TEMPERATURES WILL STILL BE
CHILLY FOR LATE MARCH WITH LOWS RANGING IN THE MID/UPPER 30S
INLAND TO THE LOWER 40S OUTER BANKS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 330 AM MON...LONG TERM PERIOD WILL FEATURE VERY
CHANGEABLE WEATHER PATTERN TYPICAL OF EARLY SPRING WITH LARGE
VARIATION IN TEMPERATURES AND AN UNSETTLED PATTERN.
MAINLY DRY CONDITIONS TUE NIGHT INTO WED WITH HIGH PRES TO THE
NORTHEAST REESTABLISHING ITSELF ACROSS E NC WITH ZONAL FLOW ALOFT.
SOME MODERATION IN TEMPS FOR TUE THOUGH STILL BELOW CLIMO WITH HIGHS
NEAR 50 NORTHEAST TO NEAR 60 SOUTHWEST UNDER PARTLY SUNNY SKIES.
LOWS NEAR CLIMO TUE NIGHT WITH READINGS IN THE 40S. CONTINUED
PREVIOUS FCST TREND WITH PCPN HOLDING OFF DURING THE DAY WED AS
RETURN FLOW BECOMES SOUTHEAST LATE IN THE DAY THOUGH LOW LEVELS
STILL DRY WITH JUST AN INC IN CLOUD COVER EXPECTED. HIGHS EXPECTED
NEAR 70 AWAY FROM THE COAST WITH 50S ON THE OUTER BANKS WITH
CONTINUED NORTHEAST BREEZE KEEPING IT COOLER HERE.
INC CHANCES FOR RAIN SHOWERS WED NIGHT AS RETURN SSW FLOW
STRENGTHENS AND RAPID INC IN LOW LEVEL MOISTURE ENSUES. SHORTWAVE
ENERGY PIVOTING AROUND LONG WAVE CENTRAL CONUS TROUGH WILL AID IN
UPR SUPPORT FOR SCT TO NUMEROUS RAIN SHOWERS.
FOR THUR...WARM AND HUMID DAY EXPECTED WITH BUILDING LOW LEVEL
THICKNESSES AND RESPONDING INC TEMPS AND DEWPOINTS EXPECTED AHEAD OF
APPROACHING STRONG COLD FRONT AND AFOREMENTIONED LONG WAVE TROUGH.
SFC INSTABILITY WILL BE PRESENT WITH PARTLY SUNNY SKIES EXPECTED
ALONG WITH SUFFICIENT DEEP LAYER SHEAR FOR THE POSSIBILITY OF
ORGANIZED THUNDER. HOWEVER...UPR SUPPORT WILL REMAIN WELL WEST OF
THE AREA AS POSTITVELY TILTED TROUGH IS SLOW TO MAKE HEADWAY TOWARDS
E NC...SO THREAT FOR SEVERE IS MARGINAL AT THIS TIME. HIGHS WILL
EASILY CLIMB INTO THE 70S...POSSIBLY HIGHER IF MORE SUNSHINE BREAKS
OUT. PRECIP THREAT WILL CONTINUE INTO THUR NIGHT AS 23/00Z
GFS/ECM/CMC IN GENERAL AGREEMENT ON A THUR NIGHT/FRI MORNING FRONTAL
PASSAGE.
FOR FRIDAY...POSITIVELY TILTED UPR TROUGH REMAINS WEST OF THE AREA
DESPITE THE SFC FRONTAL PASSAGE. MODELS INDICATE MORE SHORTWAVE
ENERGY ALOFT PRODUCING CHANCES FOR PRECIP THROUGH THE DAY AND WILL
RETAIN THE CHANCE POPS. TEMPS WILL BE NEAR CLIMO WITH HIGHS
GENERALLY IN THE 60S...WITH COOLER 50S OBX UNDER NORTHEAST SFC FLOW.
FRI NIGHT THROUGH SAT THERE IS DISAGREEMENT WITH RESPECT TO UPR
SUPPORT AS TROUGH AXIS WORKS THROUGH E NC. DETERMINISTIC GFS/CMC
CONTINUE WITH A WETTER SOLN WITH A COLD RAIN POSSIBLY MIXING WITH A
FEW SNOW SHOWERS...THOUGH LATEST 23/00Z ECMWF HAS A DRIER TREND.
WILL CONTINUE PREVIOUS CHANCE POPS AS WOULD LIKE TO SEE MORE
CONSISTENCY FROM ECMWF BEFORE MAKING LARGE SCALE CHANGES.
SUNDAY WILL BE QUITE COLD FOR LATE MARCH WITH TEMPS SOME 15-20
DEGREES BELOW CLIMO AND POSSIBLE FROST OR FREEZING CONDITIONS FOR E
NC. GROWING SEASON WILL BEGIN ACROSS ALL OF EASTERN NC ON MARCH 28.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 12Z TUESDAY/...A GENERALLY DRY SUB CLOUD LAYER
HAS PREVENTED CEILINGS FROM DROPPING DESPITE SOME LIGHT
PRECIPITATION RETURNS ON RADAR. THE BULK OF THE LIGHT RAIN HAS
OCCURRED ALONG THE SOUTHERN COAST. CEILINGS ARE CURRENTLY MVFR AT
KISO...BUT ANTICIPATE ALL CEILINGS TO BE VFR BY 15Z OR SO AS
DEWPOINTS DROP INTO THE 30S. EXPECT VFR CONDITIONS OVERNIGHT AS
DRY COOL HIGH PRESSURE SETTLES SOUTH.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...VFR CONDITIONS WILL DOMINATE TUE AND WED. NEXT
CHANCE FOR RAIN SHOWERS AND SUB VFR CONDITIONS WILL BE WED NIGHT
INTO THUR AS MOISTURE STREAMS NORTHWARD AHEAD OF STRONG COLD FRONT
SET TO PASS THROUGH BY FRIDAY MORNING. S TO SW WINDS WILL BE GUSTY
ON THURSDAY.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 655 AM MONDAY...WINDS HAVE STARTED TO INCREASE ON THE SOUNDS
AND NORTHERN WATERS OVER THE PAST COUPLE OF HOURS. THE GRADIENT
WILL INCREASE DRAMATICALLY OVER THE NEXT FEW HOURS BETWEEN LOW
PRESSURE PASSING TO OUR SOUTH AND CANADIAN HIGH PRESSURE BUILDING
DOWN FROM THE NORTH. EXPECT NORTHEAST WINDS TO INCREASE TO 20 TO
25 KNOTS OVER THE COASTAL WATERS WITH A PERIOD OF 25 TO 30 KNOT
WINDS POSSIBLE OVER PORTIONS OF THE CENTRAL WATERS THROUGH THE
MID TO LATE MORNING HOURS. ON THE SOUNDS...WINDS WILL GENERALLY BE
15 TO 25 KNOTS WITH A FEW GUSTS TO 30 KNOTS POSSIBLE THIS MORNING
ESPECIALLY. PER LATEST LOCAL NWPS/SWAN MODEL...SEAS WILL BUILD TO
AS HIGH AS 7 OR 8 FEET THROUGH THE LATE MORNING AND AFTERNOON
HOURS...ESPECIALLY CENTRAL AND NORTHERN WATERS. ONLY CHANGE TO
ADVISORIES WAS TO EXTEND FAR SOUTHERN WATERS INTO TUESDAY EVENING
WITH SEAS REMAINING ELEVATED.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...THE PRESSURE GRADIENT LOOSENS ON TUE
WITH SCA CONDITIONS ENDING. HIGH PRESSURE WILL CONTINUE TO PRODUCE
NORTHEAST WINDS IN THE 15-20 KT RANGE THROUGH TUE NIGHT. THE HIGH
WILL MOVE OFF THE COAST ON WEDNESDAY AND WINDS WILL VEER TO
SOUTHEAST LATE IN THE AFTERNOON. THE FLOW WILL CONTINUE TO VEER TO
SOUTH WEDNESDAY NIGHT AND THURSDAY AS THE HIGH MOVES EAST AND A COLD
FRONT APPROACHES FROM THE WEST. SCA CONDITIONS WILL LIKELY REDEVELOP
BY LATE WED NIGHT OR THURSDAY AS SOUTHERLY WINDS STRENGTHEN AND SEAS
BUILD ABOVE 6 FT. FRONT WILL PASS OFF THE COAST FRI MORNING WITH
WINDS TURNING NORTHERLY. THE NORTH WINDS WILL STRENGTHEN ON SATURDAY
AS STRONG COLD AIR ADVECTION MOVES INTO THE E NC WATERS WITH GUSTY
NORTH WINDS AND HIGH SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR AMZ130-
131-150.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...CTC
LONG TERM...TL
AVIATION...CTC/TL
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1036 AM CDT MON MAR 23 2015
.UPDATE...
ISSUED AT 1036 AM CDT MON MAR 23 2015
MAIN ISSUE FOR THE MORNING UPDATE WILL BE SKY COVER...AND ITS
POSSIBLE AFFECTS ON HIGH TEMPERATURES.
SURFACE LOW NOTED ALONG THE CANADIAN BORDER NORTH OF MINOT WITH A
COLD FRONT EXTENDING THROUGH SOUTHWEST NORTH DAKOTA. BEHIND THE
FRONT MVFR STRATUS HAS FILLED IN OVER THE NORTHWEST AND NORTH
CENTRAL. AHEAD OF THE FRONT...ANOTHER AREA OF MVFR TO IFR STRATUS
REMAINS OVER THE JAMES RIVER VALLEY AND INTO EASTERN NORTH DAKOTA.
LATEST HRRR INDICATES STRATUS HOLDING ON OVER THE NORTHWEST AND
CENTRAL NORTH DAKOTA THROUGH LATE MORNING...THEN QUICKLY ERODING
IN THE EARLY AFTERNOON. THE STRATUS IN THE JAMES RIVER VALLEY
NORTH INTO THE TURTLE MOUNTAINS AREA...HANGS ON THROUGH MUCH OF
THE AFTERNOON. CURRENT FORECAST HIGHS ARE LOWEST IN THESE
AREAS...SO NOT CONFIDENT ON HOW MUCH/IF ANY THESE NEED TO BE
DROPPED. THE CLOUDS OVER THE SOUTHWEST WHERE WARMEST TEMPERATURES
ARE EXPECTED...SHOULD DIMINISH QUICKLY LATE MORNING THROUGH EARLY
AFTERNOON. THUS HIGHS HERE MIGHT ALSO BE OKAY. WILL HOPEFULLY GET
A BETTER IDEA ON TEMPERATURES WITH THE LATE MORNING/EARLY
AFTERNOON UPDATE.
UPDATE ISSUED AT 641 AM CDT MON MAR 23 2015
EARLY MORNING 11-3.9 MICRON SATELLITE IMAGERY SHOWS AREAS OF
STRATUS FROM SOUTHERN SASKATCHEWAN INTO NORTHERN AND EASTERN NORTH
DAKOTA. THE STRATUS IS EXPECTED TO GRADUALLY DIMINISH
TODAY...THOUGH IT COULD BE SLOW TO LEAVE IN THE EAST WHERE THE LOW
LEVEL RELATIVE HUMIDITY VALUES PERSIST INTO EARLY AFTERNOON
ACCORDING TO THE 23.06Z NAM. WILL NOT ALTER HIGHS AT THE
MOMENT...BUT IT IS SOMETHING TO WATCH IF THE STRATUS PERSISTS
LONGER THAN EXPECTED. HELD ONTO PATCHY FOG THIS MORNING WITH A
COUPLE SPOTS ACROSS THE FORECAST AREA REPORTING SMALL REDUCTIONS
IN VISIBILITY. OVERALL...MADE ONLY MINOR CHANGES TO BLEND IN
CURRENT CONDITIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CDT MON MAR 23 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE LOW CLOUDS
THIS MORNING FAR NORTH AND SOUTH CENTRAL/SOUTHEAST...THEN
INCREASING CHANCES FOR RAIN TONIGHT WEST AND SOUTH
CENTRAL...ALONG WITH A THREAT FOR FREEZING RAIN FAR NORTHWEST.
CURRENTLY...NORTHWEST FLOW ALOFT WITH A POTENT S/WV TROUGH MOVING
EAST-SOUTHEAST INTO NORTHWESTERN MINNESOTA. SNOW CONTINUES OVER
NORTHEASTERN NORTH DAKOTA...GRAZING THE TURTLE MOUNTAIN AREA.
ELSEWHERE...MOSTLY CLEAR SOUTHWEST WITH CLOUDY SKIES FAR NORTH AND
SOUTH CENTRAL WITH LOW STRATUS. WILL LEAVE PATCHY FOG IN THE
FORECAST WITH THIS ISSUANCE AS STILL POTENTIAL FOR DEVELOPMENT
THIS MORNING.
BECOMING MOSTLY SUNNY TODAY AS LOW CLOUDS BURN OFF LATER THIS
MORNING. POSSIBLE THAT WE WILL HAVE SOME LINGERING LOW CLOUDS
ACROSS THE SOUTHEAST AND FAR NORTH...WHICH WOULD IMPACT DAYTIME
HIGHS. STRONG WAA ACROSS THE SOUTHWEST WILL SEE DAYTIME HIGHS
CLIMB WELL INTO THE 50S ALONG TO SOUTH AND WEST OF THE MISSOURI
RIVER...WITH LOW 60S PROBABLE SOUTHWEST. MODELS GENERATING DIURNAL
INSTABILITY WITH CAPE CLIMBING INTO THE HUNDREDS OVER
SOUTHEASTERN MONTANA THIS AFTERNOON. DO NOT EXPECT ANY CONVECTIVE
ACTIVITY OVER MY AREA...BUT WOULD NOT BE SURPRISED IF A FEW
LIGHTNING STRIKES POPPED UP OFF TO OUR SOUTHWEST.
UPPER LEVEL TROUGH MOVES ACROSS THE ROCKIES TONIGHT INTO THE
NORTHERN HIGH PLAINS. ASSOCIATED SFC TROUGH IN RESPONSE MOVES INTO
THE WESTERN DAKOTAS. INCREASING CHANCES FOR RAIN FAR WEST THIS
EVENING...FOLLOWED BY INCREASING CHANCES FOR RAIN WEST AND SOUTH
CENTRAL OVERNIGHT. THERE LOOKS TO BE A THREAT FOR FREEZING RAIN
ACROSS MY NORTHWEST TONIGHT IF AIR TEMPERATURES COOL TO BELOW 32F
AS MODELS SUGGEST. THIS WILL BE MENTIONED IN BOTH THE HWO AND SPS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 355 AM CDT MON MAR 23 2015
THE MAIN CONCERN IN THE LONG TERM PERIOD WILL BE THE RAIN / SNOW
CHANCES TUESDAY INTO WEDNESDAY AS LOW PRESSURE MOVES ACROSS THE
NORTHERN AND CENTRAL PLAINS. THE 00Z MODELS STILL SHOW SOME
DIFFERENCES IN REGARDS TO THE PROGRESSION OF THE SURFACE
FEATURES...THOUGH THEY GENERALLY SUGGEST TWO LOWS DEVELOPING. THE
NORTHERN LOW IS EXPECTED TO TRACK ACROSS NORTH DAKOTA...WITH THE
ECMWF A LITTLE FARTHER SOUTH THAN THE GFS. THIS CREATES SOME
UNCERTAINTY REGARDING HOW QUICKLY THE COLD AIR RETURNS AND
CONSEQUENTLY SNOW CHANCES. OVERALL...IT APPEARS MUCH OF TUESDAY
WILL SEE TEMPERATURES THROUGHOUT THE ATMOSPHERIC COLUMN SUPPORTING
RAIN...THOUGH THE FAR NORTHWEST COULD SEE A BIT MORE SNOW THAN OTHER
AREAS INITIALLY. ONCE THE COLDER AIR ARRIVES...THE HEAVIER QPF
AMOUNTS ARE FORECAST TO BE EAST OF THE CWA...SO THE OVERALL TREND OF
LESSER SNOW AMOUNTS BY THE LATEST WPC GUIDANCE LOOKS JUSTIFIED.
WILL HAVE A GENERAL AREA OF 1 TO 3 INCHES NORTH OF HIGHWAY 2....WITH
THE HIGHER AMOUNTS NEAR THE INTERNATIONAL BORDER. WINDS WILL BE
ANOTHER CONCERN AS THE LOW PASSES AND COLD AIR ADVECTION TAKES
HOLD. COULD SEE WINDS POTENTIALLY APPROACHING ADVISORY
LEVELS...ESPECIALLY ON WEDNESDAY.
THE REMAINDER OF THE LONG TERM PERIOD IS RELATIVELY QUIET WITH A
WARMING TREND INTO SATURDAY. SATURDAY LOOKS TO BE THE WARMEST DAY
OF THE LONG TERM PERIOD WITH HIGHS POTENTIALLY APPROACHING 70
DEGREES IN SOUTHWEST NORTH DAKOTA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1036 AM CDT MON MAR 23 2015
MVFR CEILING CURRENTLY AT KISN/KMOT AND KBIS...AND IFR CEILINGS AT
KJMS. WILL KEEP MVFR CEILINGS THROUGH THE MORNING KISN AND KBIS
BUT HOLD THEM INTO THE EARLY AFTERNOON KMOT AND MID AFTERNOON
KJMS...BUT WILL BRING KJMS TO MVFR FROM IFR AROUND MIDDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...CK
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
949 AM CDT MON MAR 23 2015
.UPDATE...
ISSUED AT 949 AM CDT MON MAR 23 2015
SNOW CONTINUES TO MAKE ITS WAY ACROSS THE NORTHERN RED RIVER
VALLEY. GRAND FORKS AND THEIF RIVER FALLS HAVE STARTED REPORTING
SNOW...BUT THINK THAT AMOUNTS WILL REMAIN LIGHT SO WILL KEEP THE
ADVISORY AS IT IS AND NOT SPREAD IT FURTHER SOUTH. MADE SOME
TWEAKS TO POPS AND QPF TO REFLECT CURRENT TRENDS.
UPDATE ISSUED AT 740 AM CDT MON MAR 23 2015
OBSERVER REPORTS 3.5 INCHES 12 MILES NW OF CAVALIER...WITH AT
LEAST 2 INCHES PROBABLY 3 INCHES REPORTED IN CAVALIER BY THE
SHERIFF. SNOW SHOULD CONTINUE FOR AT LEAST A FEW MORE HOURS IN
THAT AREA BEFORE THE UPPER LOW SLIDES TO THE SOUTHEAST. WILL NEED
TO ISSUE A WINTER WX ADVISORY FOR 2-5 INCHES OF SNOW FOR THE
EXTREME NORTHERN VALLEY.
UPDATE ISSUED AT 642 AM CDT MON MAR 23 2015
WATER VAPOR IMAGERY SHOWS SMALL BUT INTENSE UPPER WAVE JUST NORTH
OF THE INTERNATIONAL BORDER...ABOUT TO CROSS INTO THE STATES.
BURST OF SNOW AHEAD OF THIS FEATURE APPEARS TO HAVE GIVEN THE
CALALIER AREA AROUND AN INCH OR SO OF SNOWFALL (JUDGING FROM THE
WEBCAM). HRRR/RAP GUIDANCE CONTINUES TO SUPPORT THE ONGOING
FORECAST OF AN INCH OR TWO OF SNOW (POSSIBLY 3 INCHES CLOSER TO
CANADA) FROM THE NORTHERN VALLEY INTO THE THIEF RIVER FALLS AREA
BY NOON. ADJUSTED POPS TO ACCOUNT FOR A SLIGHTLY FASTER
PROGRESSION GIVEN CURRENT RADAR IMAGERY...OTHERWISE NO OTHER
CHANGES ARE PLANNED.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 358 AM CDT MON MAR 23 2015
THE UPPER LOW JUST NORTH OF THE INTERNATIONAL BORDER WILL CONTINUE
TO PROPAGATE SOUTHEAST TODAY. THE LATEST MODEL GUIDANCE SUGGESTS
THIS FEATURE WILL TRACK INTO CENTRAL MINNESOTA THIS AFTERNOON AND
THEN SHEAR OUT. ADJUSTED POPS/QPF/SNOW AMOUNTS TO THE LATEST
HRRR/RAP GUIDANCE. THIS LED TO SNOW AMOUNTS NEAR 2 INCHES ACROSS
THE NORTHERN VALLEY NEAR THE INTERNATIONAL BORDER...TO AROUND OR
LESS THAN AN INCH INTO THE THIEF RIVER FALLS AREA BY NOON. DO NOT
EXPECT MUCH ACCUMULATION DURING THE AFTERNOON HOURS DUE TO A
WARMER LOW LEVEL AIRMASS (COULD ALSO BE MORE A RAIN/SNOW MIX AFTER
NOON). AREAS TO THE WEST OF THE EXPECTED TRACK OF THIS SYSTEM
SHOULD BE DRY...WITH MAX TEMPS INTO THE 40S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 358 AM CDT MON MAR 23 2015
TUESDAY-WEDNESDAY...00Z MODELS ARE IN BETTER AGREEMENT THAN PAST
RUNS WITH THE EXPECTED STORM SYSTEM. THE MAIN TREND IS FOR MORE OF
A SPLIT FLOW...WITH LESS INTERACTION BETWEEN THE SOUTHERN AND
NORTHERN UPPER WAVES. THE LATEST GUIDANCE IS QUICKER WITH THE
SOUTHERN WAVE...AND SLOWER WITH THE NORTHERN WAVE. THIS SCENARIO
LEADS TO A MUCH WEAKER INVERTED TROUGH...AND MUCH LESS QPF (IF
ANY). THIS SYSTEM IS STILL A COUPLE DAYS OUT...AND DETAILS WILL
DEPEND ON THE ACTUAL TIMING OF THE NORTHERN AND SOUTHERN WAVES AND
THEIR INTERACTIONS WITH EACH OTHER. WITH THAT SAID...OPTED TO MAKE
VERY LITTLE CHANGE TO ONGOING POPS UNTIL MODELS SHOW MORE
CONSISTENCY...BUT DID TREND QPF LOWER. PRECIP STILL LOOKS LIKE IT
WOULD BEGIN AS RAIN...THEN CHANGE TO SNOW BY WED MORNING. WILL
ALSO NEED TO KEEP AN EYE ON WIND SPEEDS ON WED...AND IF THEY ARE
STRONG AND OCCUR WITH FALLING SNOW THIS COULD LEAD TO SOME
IMPACTS.
THURSDAY-SUNDAY...UPPER AIR PATTERN AMPLIFIES THIS PERIOD. LONG
WAVE TROUGH OVER EASTERN CANADA AMPLIFIES QUITE A BIT THIS PERIOD
WHILE THE LONG WAVE UPPER HIGH OVER WESTERN NORTH AMERICA
AMPLIFIES BUT TO A LESSER EXTENT. AT 84 HOURS THE ECMWF WAS A
LITTLE FASTER SOLUTION THAN THE GFS. BY THE END OF THE PERIOD THE
GFS IS THE FASTER SOLUTION. GFS AND ECMWF HAVE BEEN TRENDING
FARTHER WEST/SOUTHWEST OVER THE LAST COUPLE MODEL RUNS. WILL BLEND
THE GFS AND ECMWF.
HIGH TEMPS HAVE BEEN DECREASED ONE OR TWO DEGREES FOR THU AND FRI
AND INCREASE TWO TO THREE DEGREES FOR SAT. LITTLE CHANGE ON SUN
FROM YESTERDAYS FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 642 AM CDT MON MAR 23 2015
IFR/MVFR CIGS DEVELOPING TO THE SOUTH AND WEST OF THE POTENT UPPER
LOW NEAR THE NORTHERN VALLEY. ANTICIPATE THESE CIGS TO AFFECT MUCH
OF THE REGION GIVEN LATEST TRENDS AND RAP GUIDANCE...WITH
IMPROVING CONDITIONS THIS AFTERNOON. -SN NOW EXPECTED TO IMPACT
KTVF...AND POSSIBLY KGFK.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR NDZ008-
016.
MN...WINTER WEATHER ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR MNZ004-
007.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
740 AM CDT MON MAR 23 2015
.UPDATE...
ISSUED AT 740 AM CDT MON MAR 23 2015
OBSERVER REPORTS 3.5 INCHES 12 MILES NW OF CAVALIER...WITH AT
LEAST 2 INCHES PROBABLY 3 INCHES REPORTED IN CAVALIER BY THE
SHERIFF. SNOW SHOULD CONTINUE FOR AT LEAST A FEW MORE HOURS IN
THAT AREA BEFORE THE UPPER LOW SLIDES TO THE SOUTHEAST. WILL NEED
TO ISSUE A WINTER WX ADVISORY FOR 2-5 INCHES OF SNOW FOR THE
EXTREME NORTHERN VALLEY.
UPDATE ISSUED AT 642 AM CDT MON MAR 23 2015
WATER VAPOR IMAGERY SHOWS SMALL BUT INTENSE UPPER WAVE JUST NORTH
OF THE INTERNATIONAL BORDER...ABOUT TO CROSS INTO THE STATES.
BURST OF SNOW AHEAD OF THIS FEATURE APPEARS TO HAVE GIVEN THE
CALALIER AREA AROUND AN INCH OR SO OF SNOWFALL (JUDGING FROM THE
WEBCAM). HRRR/RAP GUIDANCE CONTINUES TO SUPPORT THE ONGOING
FORECAST OF AN INCH OR TWO OF SNOW (POSSIBLY 3 INCHES CLOSER TO
CANADA) FROM THE NORTHERN VALLEY INTO THE THIEF RIVER FALLS AREA
BY NOON. ADJUSTED POPS TO ACCOUNT FOR A SLIGHTLY FASTER
PROGRESSION GIVEN CURRENT RADAR IMAGERY...OTHERWISE NO OTHER
CHANGES ARE PLANNED.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 358 AM CDT MON MAR 23 2015
THE UPPER LOW JUST NORTH OF THE INTERNATIONAL BORDER WILL CONTINUE
TO PROPAGATE SOUTHEAST TODAY. THE LATEST MODEL GUIDANCE SUGGESTS
THIS FEATURE WILL TRACK INTO CENTRAL MINNESOTA THIS AFTERNOON AND
THEN SHEAR OUT. ADJUSTED POPS/QPF/SNOW AMOUNTS TO THE LATEST
HRRR/RAP GUIDANCE. THIS LED TO SNOW AMOUNTS NEAR 2 INCHES ACROSS
THE NORTHERN VALLEY NEAR THE INTERNATIONAL BORDER...TO AROUND OR
LESS THAN AN INCH INTO THE THIEF RIVER FALLS AREA BY NOON. DO NOT
EXPECT MUCH ACCUMULATION DURING THE AFTERNOON HOURS DUE TO A
WARMER LOW LEVEL AIRMASS (COULD ALSO BE MORE A RAIN/SNOW MIX AFTER
NOON). AREAS TO THE WEST OF THE EXPECTED TRACK OF THIS SYSTEM
SHOULD BE DRY...WITH MAX TEMPS INTO THE 40S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 358 AM CDT MON MAR 23 2015
TUESDAY-WEDNESDAY...00Z MODELS ARE IN BETTER AGREEMENT THAN PAST
RUNS WITH THE EXPECTED STORM SYSTEM. THE MAIN TREND IS FOR MORE OF
A SPLIT FLOW...WITH LESS INTERACTION BETWEEN THE SOUTHERN AND
NORTHERN UPPER WAVES. THE LATEST GUIDANCE IS QUICKER WITH THE
SOUTHERN WAVE...AND SLOWER WITH THE NORTHERN WAVE. THIS SCENARIO
LEADS TO A MUCH WEAKER INVERTED TROUGH...AND MUCH LESS QPF (IF
ANY). THIS SYSTEM IS STILL A COUPLE DAYS OUT...AND DETAILS WILL
DEPEND ON THE ACTUAL TIMING OF THE NORTHERN AND SOUTHERN WAVES AND
THEIR INTERACTIONS WITH EACH OTHER. WITH THAT SAID...OPTED TO MAKE
VERY LITTLE CHANGE TO ONGOING POPS UNTIL MODELS SHOW MORE
CONSISTENCY...BUT DID TREND QPF LOWER. PRECIP STILL LOOKS LIKE IT
WOULD BEGIN AS RAIN...THEN CHANGE TO SNOW BY WED MORNING. WILL
ALSO NEED TO KEEP AN EYE ON WIND SPEEDS ON WED...AND IF THEY ARE
STRONG AND OCCUR WITH FALLING SNOW THIS COULD LEAD TO SOME
IMPACTS.
THURSDAY-SUNDAY...UPPER AIR PATTERN AMPLIFIES THIS PERIOD. LONG
WAVE TROUGH OVER EASTERN CANADA AMPLIFIES QUITE A BIT THIS PERIOD
WHILE THE LONG WAVE UPPER HIGH OVER WESTERN NORTH AMERICA
AMPLIFIES BUT TO A LESSER EXTENT. AT 84 HOURS THE ECMWF WAS A
LITTLE FASTER SOLUTION THAN THE GFS. BY THE END OF THE PERIOD THE
GFS IS THE FASTER SOLUTION. GFS AND ECMWF HAVE BEEN TRENDING
FARTHER WEST/SOUTHWEST OVER THE LAST COUPLE MODEL RUNS. WILL BLEND
THE GFS AND ECMWF.
HIGH TEMPS HAVE BEEN DECREASED ONE OR TWO DEGREES FOR THU AND FRI
AND INCREASE TWO TO THREE DEGREES FOR SAT. LITTLE CHANGE ON SUN
FROM YESTERDAYS FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 642 AM CDT MON MAR 23 2015
IFR/MVFR CIGS DEVELOPING TO THE SOUTH AND WEST OF THE POTENT UPPER
LOW NEAR THE NORTHERN VALLEY. ANTICIPATE THESE CIGS TO AFFECT MUCH
OF THE REGION GIVEN LATEST TRENDS AND RAP GUIDANCE...WITH
IMPROVING CONDITIONS THIS AFTERNOON. -SN NOW EXPECTED TO IMPACT
KTVF...AND POSSIBLY KGFK.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR NDZ008-
016.
MN...WINTER WEATHER ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR MNZ004-
007.
&&
$$
UPDATE...TG
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
642 AM CDT MON MAR 23 2015
.UPDATE...
ISSUED AT 642 AM CDT MON MAR 23 2015
WATER VAPOR IMAGERY SHOWS SMALL BUT INTENSE UPPER WAVE JUST NORTH
OF THE INTERNATIONAL BORDER...ABOUT TO CROSS INTO THE STATES.
BURST OF SNOW AHEAD OF THIS FEATURE APPEARS TO HAVE GIVEN THE
CALALIER AREA AROUND AN INCH OR SO OF SNOWFALL (JUDGING FROM THE
WEBCAM). HRRR/RAP GUIDANCE CONTINUES TO SUPPORT THE ONGOING
FORECAST OF AN INCH OR TWO OF SNOW (POSSIBLY 3 INCHES CLOSER TO
CANADA) FROM THE NORTHERN VALLEY INTO THE THIEF RIVER FALLS AREA
BY NOON. ADJUSTED POPS TO ACCOUNT FOR A SLIGHTLY FASTER
PROGRESSION GIVEN CURRENT RADAR IMAGERY...OTHERWISE NO OTHER
CHANGES ARE PLANNED.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 358 AM CDT MON MAR 23 2015
THE UPPER LOW JUST NORTH OF THE INTERNATIONAL BORDER WILL CONTINUE
TO PROPAGATE SOUTHEAST TODAY. THE LATEST MODEL GUIDANCE SUGGESTS
THIS FEATURE WILL TRACK INTO CENTRAL MINNESOTA THIS AFTERNOON AND
THEN SHEAR OUT. ADJUSTED POPS/QPF/SNOW AMOUNTS TO THE LATEST
HRRR/RAP GUIDANCE. THIS LED TO SNOW AMOUNTS NEAR 2 INCHES ACROSS
THE NORTHERN VALLEY NEAR THE INTERNATIONAL BORDER...TO AROUND OR
LESS THAN AN INCH INTO THE THIEF RIVER FALLS AREA BY NOON. DO NOT
EXPECT MUCH ACCUMULATION DURING THE AFTERNOON HOURS DUE TO A
WARMER LOW LEVEL AIRMASS (COULD ALSO BE MORE A RAIN/SNOW MIX AFTER
NOON). AREAS TO THE WEST OF THE EXPECTED TRACK OF THIS SYSTEM
SHOULD BE DRY...WITH MAX TEMPS INTO THE 40S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 358 AM CDT MON MAR 23 2015
TUESDAY-WEDNESDAY...00Z MODELS ARE IN BETTER AGREEMENT THAN PAST
RUNS WITH THE EXPECTED STORM SYSTEM. THE MAIN TREND IS FOR MORE OF
A SPLIT FLOW...WITH LESS INTERACTION BETWEEN THE SOUTHERN AND
NORTHERN UPPER WAVES. THE LATEST GUIDANCE IS QUICKER WITH THE
SOUTHERN WAVE...AND SLOWER WITH THE NORTHERN WAVE. THIS SCENARIO
LEADS TO A MUCH WEAKER INVERTED TROUGH...AND MUCH LESS QPF (IF
ANY). THIS SYSTEM IS STILL A COUPLE DAYS OUT...AND DETAILS WILL
DEPEND ON THE ACTUAL TIMING OF THE NORTHERN AND SOUTHERN WAVES AND
THEIR INTERACTIONS WITH EACH OTHER. WITH THAT SAID...OPTED TO MAKE
VERY LITTLE CHANGE TO ONGOING POPS UNTIL MODELS SHOW MORE
CONSISTENCY...BUT DID TREND QPF LOWER. PRECIP STILL LOOKS LIKE IT
WOULD BEGIN AS RAIN...THEN CHANGE TO SNOW BY WED MORNING. WILL
ALSO NEED TO KEEP AN EYE ON WIND SPEEDS ON WED...AND IF THEY ARE
STRONG AND OCCUR WITH FALLING SNOW THIS COULD LEAD TO SOME
IMPACTS.
THURSDAY-SUNDAY...UPPER AIR PATTERN AMPLIFIES THIS PERIOD. LONG
WAVE TROUGH OVER EASTERN CANADA AMPLIFIES QUITE A BIT THIS PERIOD
WHILE THE LONG WAVE UPPER HIGH OVER WESTERN NORTH AMERICA
AMPLIFIES BUT TO A LESSER EXTENT. AT 84 HOURS THE ECMWF WAS A
LITTLE FASTER SOLUTION THAN THE GFS. BY THE END OF THE PERIOD THE
GFS IS THE FASTER SOLUTION. GFS AND ECMWF HAVE BEEN TRENDING
FARTHER WEST/SOUTHWEST OVER THE LAST COUPLE MODEL RUNS. WILL BLEND
THE GFS AND ECMWF.
HIGH TEMPS HAVE BEEN DECREASED ONE OR TWO DEGREES FOR THU AND FRI
AND INCREASE TWO TO THREE DEGREES FOR SAT. LITTLE CHANGE ON SUN
FROM YESTERDAYS FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 642 AM CDT MON MAR 23 2015
IFR/MVFR CIGS DEVELOPING TO THE SOUTH AND WEST OF THE POTENT UPPER
LOW NEAR THE NORTHERN VALLEY. ANTICIPATE THESE CIGS TO AFFECT MUCH
OF THE REGION GIVEN LATEST TRENDS AND RAP GUIDANCE...WITH
IMPROVING CONDITIONS THIS AFTERNOON. -SN NOW EXPECTED TO IMPACT
KTVF...AND POSSIBLY KGFK.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS MIAMI FL
212 PM EDT MON MAR 23 2015
.AVIATION...
SOUTHWESTERLY WINDS SHOULD PREVAIL THROUGH THE REMAINDER OF THE
AFTERNOON AS A COLD FRONT APPROACHES FROM THE WEST. SHOWERS OUT
AHEAD OF THIS FRONT SHOULD BEGIN MOVING INTO THE TAF SITES OVER
THE NEXT FEW HOURS. ISOLATED THUNDERSTORMS ARE POSSIBLE BUT
BELIEVE COVERAGE WILL BE RATHER SPARSE AND THEREFORE DID NOT
MENTION IN TAFS FOR NOW. WINDS SHOULD BECOME VARIABLE TO LIGHT NNW
AS THE FRONT SLOWLY PUSHES INTO THE TAF SITES LATER TONIGHT. COULD
BE SOME ISOLATED MVFR/IFR CIGS AT KAPF OVERNIGHT...LEFT MENTION
OUR FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 1014 AM EDT MON MAR 23 2015/
UPDATE...
COLD FRONT APPROACHING CENTRAL AND SOUTHERN FLORIDA TODAY AND
TONIGHT FROM THE GULF OF MEXICO, WITH UPPER WAVE AHEAD OF IT, MAY
GENERATE SCATTERED SHOWERS ESPECIALLY ACROSS THE NORTHERN HALF OF
THE CWA THIS AFTERNOON. AS PREVIOUSLY MENTIONED, THUNDER CHANCES
LOOK SMALL, WITH MEAGER MIDLEVEL LAPSE RATES. FORECAST IN GOOD
SHAPE AND NO CHANGES NECESSARY.
PREV DISCUSSION... /ISSUED 422 AM EDT MON MAR 23 2015/
DISCUSSION...
A SURFACE LOW CONTINUES TO DEVELOP ALONG THE FLORIDA PANHANDLE
WITH THE TRAILING COLD FRONT ENTERING THE CENTRAL TO EASTERN GULF.
THE GLOBAL MODEL CONSENSUS CONTINUES TO BRING THIS SYSTEM TO THE
EAST TODAY WITH THE FRONT EXPECTED TO APPROACH SOUTH FLORIDA
AROUND 00Z THIS EVENING THEN ACROSS SOUTH FLORIDA AND ADJACENT
WATERS TONIGHT AND STALL ACROSS THE SOUTHERN TIP OF THE PENINSULA
OR FLORIDA STRAITS TUESDAY MORNING.
FOR TODAY...AS THE AFOREMENTIONED FRONT CONTINUES TO PASS ACROSS
THE EASTERN GULF TODAY CHANCES OF SHOWERS AHEAD OF THE FRONT WILL
CONTINUE THROUGH THE MORNING HOURS INTO THE AFTERNOON...WHEN THE
GREATEST COVERAGE OF SHOWERS IS EXPECTED. THUS FAR SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON...WITH A GENERAL CONSENSUS OF THE GLOBAL MODELS AND SHORT
RANGE ENSEMBLE ALTHOUGH THE HRRR MODEL INDICATES LESS COVERAGE AND
IS SLOWER IN SHOWER DEVELOPMENT. ONLY ISOLATED THUNDERSTORM
ACTIVITY IS FORECAST THIS AFTERNOON WITH THE GUIDANCE CONTINUING
TO SUGGEST THAT MID LEVEL TEMPERATURES...LAPSE RATES AND
INSTABILITY IS NOT SUFFICIENT TO SUPPORT ORGANIZED CONVECTION.
HOWEVER THE GUIDANCE DOES INDICATE THAT THE DEEPER LAYERED
MOISTURE AHEAD OF THE FRONT MAY NOT REACH THE PENINSULA UNTIL THE
AFTERNOON HOURS AND SUFFICIENT DAY TIME HEATING COULD TRIGGER SOME
ISOLATED THUNDERSTORMS. THE FORECAST LOW LEVEL WIND PROFILE INDICATES
A PROFILE SUPPORTIVE OF GUSTY WINDS WITH ANY THUNDERSTORM ACTIVITY
BUT IS NOT EXPECTED TO BE BE AN OVERALL THREAT WITH LOW LEVEL
SHEAR NOT SIGNIFICANT. LASTLY...WITH SOUTHWESTERLY WINDS EXPECTED
ACROSS THE PENINSULA THE EAST COAST SEA BREEZE SHOULD BE
SUPPRESSED THIS AFTERNOON...BUT JUST ALONG THE IMMEDIATE COAST IF
THE WINDS BECOME SOUTHEASTERLY THEN THE LOW LEVEL WIND PROFILE
MIGHT SUPPORT A SHORT LIVED FUNNEL CLOUD BUT CONFIDENCE IS LOW.
FOR TUESDAY...THE BOUNDARY AND ASSOCIATED MOISTURE IS FORECAST TO
STALL ACROSS THE FLORIDA STRAITS OR SOUTHERN TIP OF THE PENINSULA
WITH SOME ISOLATED SHOWERS POSSIBLE BUT MAINLY EXPECTED ACROSS THE
ATLANTIC WATERS.
FOR WEDNESDAY THROUGH FRIDAY...BY WEDNESDAY THE SURFACE AND LOW
LEVEL WINDS ARE FORECAST TO BECOME MORE SOUTHERLY WITH THE
BOUNDARY AND ASSOCIATED MOISTURE LIFTING NORTHWARD WITH MAINLY
AFTERNOON SHOWERS FORECAST THROUGH THIS PERIOD.
FOR THE EXTENDED FORECAST...FOR SEVERAL DAYS A STRONG COLD FRONT
HAS BEEN FORECAST TO AFFECT THE REGION THIS UPCOMING WEEKEND WITH
THE GLOBAL MODELS CONTINUING TO FORECAST THIS SCENARIO.
HOWEVER...WHILE THERE IS STILL GENERAL CONSENSUS THE TIMING OF THE
FRONTAL PASSAGE HAS BEEN SLOWED DOWN AND IS NOW FORECAST TO PASS
ACROSS SOUTH FLORIDA AND REGIONAL WATERS ON SATURDAY THEN EXIT THE
REGION SUNDAY NIGHT...ALMOST A 24 HOUR DIFFERENCE FROM PREVIOUS
GUIDANCE. EXTENDED GUIDANCE INDICATES HIGHS ON SUNDAY ONLY IN THE
LOWER 70S...WILL HAVE TO WAIT AND SEE HOW THIS SCENARIO CHANGES IN
FUTURE GUIDANCE.
MARINE...
ISOLATED THUNDERSTORMS ARE FORECAST ACROSS THE REGIONAL WATERS FOR
THIS AFTERNOON AND EARLY EVENING HOURS. IN GENERAL WINDS FORECAST
TO BE 15 KNOTS OR LESS THROUGH MID-WEEK WITH SEAS REMAINING WELL
BELOW ADVISORY LEVELS. WITH THE FORECAST PASSAGE OF A STRONG COLD
FRONT THIS UPCOMING WEEKEND SEAS COULD REACH NEAR ADVISORY
LEVELS...BUT TIMING IS DIFFICULT WITH VARYING GUIDANCE AND WILL
HAVE TO WAIT FOR FURTHER GUIDANCE CONSENSUS FOR TIMING PURPOSES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 69 87 70 87 / 30 10 10 20
FORT LAUDERDALE 71 84 71 84 / 20 10 10 20
MIAMI 71 87 71 85 / 20 10 10 20
NAPLES 69 84 67 85 / 20 10 0 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
339 PM CDT MON MAR 23 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 339 PM CDT MON MAR 23 2015
OVERNIGHT FORECAST BECOMING COMPLICATED BY STRATUS DEVELOPMENT
TODAY AND MUCH COOLER HIGHS THAN ANTICIPATED. WITH NORTHEAST FLOW
AT THE SURFACE...DEW POINTS WILL REMAIN IN THE MID TO UPPER 20S FOR
THE OVERNIGHT HOURS UNTIL WINDS BECOME MORE SOUTHEAST AFTER 06Z. THIS
SHOULD ACT TO CAP ANY COOLING OVER THE SOUTH AND ACTUALLY RESULT IN
A EITHER STEADY OR A SLOW RISE IN TEMPERATURE AND DEW POINTS OVER
THE REGION BY 12Z. SOUNDINGS CONTINUE TO SHOW DRY AIR IN THE
FORECAST AREA WILL NEED TO BE OVERCOME PRIOR TO ANY PRECIPITATION
REACHING THE GROUND. THE GFS/NAM ARE MOST AGGRESSIVE WITH
SATURATION...THOUGH THE GFS HAS BACKED OFF A BIT ON THE ONSET OF
PRECIPITATION. THE EURO HAS BEEN SIMILAR IN THE PAST 2 MODEL
SOLUTIONS IN DELAYING MOST OF THE PRECIPITATION WITH THE EXCEPTION
OF THE FAR SOUTH UNTIL 09-12Z. AFTER LOOKING AT THE HRRR AND SEEING
THAT THE MESO SCALE MODELS ARE CONTINUING WITH AN EARLIER
ONSET...HAVE TAKEN A BLEND OF THE EURO/GFS SOLUTIONS. BACKED OFF A
BIT ON THE ONSET FROM THE PREVIOUS PACKAGE AND ALSO HAVE TRIMMED
BACK THUNDER CHANCES OVER THE SOUTH WITH ONLY THE FAR SOUTH LIKELY
TO SEE ANY ISO THUNDER THROUGH 12Z. THOUGH MOST OF ANY PRECIPITATION
THAT FALLS SHOULD REMAIN LIQUID...THERE IS STILL A RISK FOR SOME
LIGHT FREEZING RAIN ON THE NORTHERN EDGE OF THE PRECIPITATION SHIELD
AND OVER SOUTHEAST SECTIONS AS THE PRECIPITATION COMMENCES. THIS IS
MAINLY DUE TO TODAYS LACK OF DAYTIME HEATING...THE RELATIVELY DRY
AIR AND THE EXPECTATION THAT OVERNIGHT LOWS OVER THOSE AREAS WILL
LIKELY BE AT OR JUST BELOW THE FREEZING MARK BY SUNRISE. WITH
LIMITED MOISTURE EXPECTED OVERNIGHT...WILL NOT HAVE ANY HEADLINES AT
THIS TIME DUE TO THE POTENTIAL OF MAINLY VERY LIGHT ACCUMULATIONS OF
A HUNDREDTH OR TWO. LOWS WILL RANGE FROM THE 20S NORTHEAST TO THE
LOWER TO MID 30S OVER THE SOUTHWEST.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 339 PM CDT MON MAR 23 2015
PRECIPITATION EXPECTED TO BE ONGOING ACROSS THE SOUTHERN HALF OF
THE CWA AND WILL CONTINUE TO SPREAD NORTH ACROSS THE REMAINDER OF
THE CWA TUESDAY AS A DOUBLE-BARRELED UPPER LEVEL SYSTEM IMPACTS
THE REGION. INITIAL WAVE ROTATING THROUGH THE BASE OF THE OTHER
LOW TO SWING THROUGH IOWA LATE TUESDAY INTO TUESDAY NIGHT BRINGING
THE MAJORITY OF THE CHANGES OF PRECIPITATION THROUGH WEDNESDAY
NIGHT. WARM FRONT ALOFT TO LIFT NORTHWARD THROUGH THE CWA...WAA
AND MOISTURE ADVECTION IN PLACE ACROSS MUCH OF THE AREA TUESDAY.
STILL EXPECTING A MAIN AREA OF WAA PRECIP TO LIFT THROUGH THE CWA
TUESDAY MORNING...WITH A DRY PERIOD ACROSS PORTIONS OF
CENTRAL/SOUTHERN IOWA MOST LIKELY LATER TUESDAY MORNING INTO EARLY
AFTERNOON. SHOWER AND POTENTIAL ISOLATED THUNDERSTORM
REDEVELOPMENT EXPECTED IN THE AFTERNOON HOURS...AS THE MAIN UPPER
LOW MOVES OVERHEAD. WIDESPREAD PRECIPITATION EXPECTED ACROSS THE
ENTIRE CWA WITH THE MAIN LOW MOVING THROUGH...WITH PRECIPITATION
EXPECTED TO TAPER OFF FROM WEST TO EAST TUESDAY EVENING AS THE
UPPER LOW PUSHES EAST NORTHEAST INTO THE GREAT LAKES REGION.
CONTINUE TO SEE CHANCES FOR ELEVATED THUNDER ACROSS THE SOUTHERN
HALF OF THE CWA TUESDAY INTO TUESDAY EVENING. DYNAMIC COOLING OF
THE COLUMN WITH MORE INTENSE PRECIPITATION AREAS SHOULD ALLOW FOR
A MIXING OF RAIN/SNOW OR COMPLETE CHANGEOVER TO ALL SNOW ACROSS
THE FAR NORTHERN AREAS LATE TUESDAY AFTERNOON INTO TUESDAY
EVENING. A QUICK INCH OR TWO OF SNOW IS POSSIBLE BEFORE
PRECIPITATION CHANCES TAPER OFF TUESDAY EVENING. WIDESPREAD HALF
INCH QPF AMOUNTS CAN BE EXPECTED FROM THIS SYSTEM.
SECOND LOBE OF THE UPPER LEVEL SYSTEM TO DROP SOUTHWARD TOWARD THE
AREA WEDNESDAY...WITH A COLD FRONT DROPPING THROUGH THE CWA. MAY
HAVE SOME PRECIPITATION FORM ALONG AND AHEAD OF THE COLD FRONT BY
LATE AFTERNOON ACROSS FAR SOUTHERN IOWA. ARCTIC HIGH PRESSURE TO
THEN BUILD INTO THE REGION FOR THURSDAY INTO FRIDAY...WITH H85
TEMPS DROPPING INTO THE TEENS BELOW CELSIUS. THIS SHOULD ALLOW
TEMPS ACROSS THE AREA TO REMAIN WELL BELOW AVERAGE TO CLOSE OUT
THE WEEK. THE HIGH QUICKLY SHOVES SOUTHEAST THROUGH AS THE THERMAL
RIDGE BUILDS IN ALOFT OVER THE UPCOMING WEEKEND WITH UPPER LEVEL
RIDGING BUILDING INTO THE CENTRAL US. THEREFORE TEMPS SHOULD WARM
BACK TO NEAR THE SEASONAL AVERAGES OR ABOVE BY SUNDAY AND INTO
EARLY NEXT WEEK.
&&
.AVIATION...23/18Z
ISSUED AT 1239 PM CDT MON MAR 23 2015
MAIN CONCERNS CONTINUE TO BE STRATUS FIELD AND CIGS THROUGH
06Z ALONG WITH EVENTUAL PRECIP CHANCES TOWARD 12Z. NORTHEAST FLOW
HAS ALLOWED FOR COOLER TEMPS AND STRATUS TO HOLD ONTO CENTRAL AND
EASTERN AREAS FOR NOW...OVERNIGHT APPROACHING SYSTEM WILL NEED TO
OVERCOME DRY AIR ALOFT PRIOR TO PRECIP ONSET. OVER THE SOUTHEAST
THERE CONTINUES TO BE A THREAT FOR -FRZA BASED ON COOLING TONIGHT
WITH IS0 TO SCT THUNDER ALSO POSSIBLE AFT 13Z AS INSTABILITY
DEVELOPS AT MID LEVELS. HAVE ADDED 3 HOUR PERIOD OF -FZRA TO KOTM
PRIOR TO POTENTIAL THUNDER. ELSEWHERE...OVER THE NORTH CIGS TO
REMAIN LOW AND PRECIP DELAYED TOWARD END OF PERIOD. /REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...BEERENDS
AVIATION...REV
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1245 PM EDT MON MAR 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 510 AM EDT MON MAR 23 2015
QUIET WEATHER WILL CONTINUE THRU THE SHORT TERM. WATER VAPOR IMAGERY
AND RAP ANALYSIS SHOW A COUPLE OF SHORTWAVES MOVING THRU THE NW FLOW
OVER THE NRN PLAINS. ONE WAVE IS MOVING ACROSS IA/SRN MN WITH A
SECOND MORE WELL-DEFINED WAVE TO THE NW IN SRN MANITOBA. ALTHOUGH
THE NRN WAVE IS MORE DEFINED...THE SRN WAVE IS PRODUCING MORE
SIGNIFICANT PCPN DUE TO THE COMBINATION OF BETTER MOISTURE AND MUCH
STRONGER FGEN. NOTHING MORE THAN SOME HIGH CLOUDS HAVE SPREAD INTO
UPPER MI OVERNIGHT ON THE NRN EDGE OF THE SRN WAVE. WITH HIGH PRES
CENTERED JUST NE OF LAKE SUPERIOR DOMINATING THE UPPER LAKES...WINDS
HAVE BEEN LIGHT/CALM ACROSS THE FCST AREA DURING THE NIGHT. THIS HAS
ALLOWED TEMPS IN TRADITIONAL COLD SPOTS TO DROP OFF INTO THE SINGLE
DIGITS ABOVE ZERO OVER THE E WHERE CLOUDS HAVE BEEN THINNEST.
ALTHOUGH UPSTREAM SHORTWAVE IN SRN MANITOBA IS WELL-DEFINED NOW AND
HAS AN ASSOCIATED AREA OF SNOW...MODELS ARE IN EXCELLENT AGREEMENT
SHOWING THIS WAVE WEAKENING AND SHEARING SE IN THE CONFLUENT FLOW
BTWN DEPARTING TROF IN SE CANADA/NE CONUS AND BUILDING RIDGE MOVING
OUT OVER THE NRN PLAINS IN ADVANCE OF COMPLEX OF SHORTWAVE ENERGY
MOVING ACROSS THE PACIFIC NW/NRN ROCKIES. SO...WHILE CURRENT LOOK OF
THE WAVE BRINGS SOME CONCERN THAT -SN/FLURRIES COULD STILL REACH THE
FAR WRN FCST AREA THIS EVENING...WILL MAINTAIN A DRY FCST SINCE
MODELS ARE IN SUCH GOOD AGREEMENT ON THE PCPN DISSIPATING. THE DRY
FCST IS STRONGLY SUPPORTED BY THE VERY DRY ANTECEDANT AIR MASS OVER
THE AREA PER OBSERVED 00Z SOUNDINGS AT KINL/KGRB. THIS DRY AIR MASS
WILL BE EVEN MORE DIFFICULT TO OVERCOME SINCE THE WAVE WILL BE
WEAKENING.
MAINLY HIGH CLOUDS AFFECTING THE AREA TODAY WILL CLEAR OUT TONIGHT
AS FCST SOUNDINGS SHOW NOTABLE DRYING IN THE UPPER LEVELS AS
MID/UPPER LEVEL RIDGE APPROACHES. WITH HIGH PRES JUST E OF THE AREA
TODAY...LIGHT EASTERLY WINDS WILL TAKE ON A LAKE BREEZE COMPONENT TO
KEEP AREAS NEAR THE GREAT LAKES COOLER...THOUGH THIS COOLING WILL BE
MORE LIMITED NEAR THE WRN SHORE OF UPPER MI. EXPECT HIGH TEMPS TODAY
TO RANGE FROM THE UPPER 20S/AROUND 30F TO AROUND 40F. IT WILL BE
COOLEST OVER THE E...NEAR LAKE SUPERIOR FROM THE KEWEENAW EASTWARD
AND NEAR LAKE MICHIGAN...AND IT WILL BE WARMEST OVER THE FAR W WHERE
DOWNSLOPING WILL AID WARMING. LEANED TOWARD THE LOWER SIDE OF
GUIDANCE TONIGHT GIVEN EXPECTED CLEARING SKIES AND CONTINUED LIGHT
WINDS. THE COLDEST BIAS CORRECTED GUIDANCE HAS MINS BLO ZERO TONIGHT
AT SOME OF THE USUAL COLD SPOTS. THAT SEEMS TOO LOW GIVEN LIGHT
SOUTHERLY FLOW AND CONTINUED MODERATION OF AIR MASS. IF ANY
LOCATIONS DO FALL SUBZERO...IT WOULD OCCUR OVER THE FAR ERN FCST
AREA CLOSER TO DEPARTING HIGH PRES. IN GENERAL...EXPECT SOME SINGLE
DIGITS ABOVE ZERO IN THE INTERIOR CNTRL AND E. OTHERWISE...MINS WILL
BE IN THE TEENS WITH SOME LOWER 20S W.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 228 AM EDT MON MAR 23 2015
AFTERNOON HIGHS TUESDAY WILL BE ON AVERAGE 10F WARMER THAN TODAY.
THIS WILL BE THANKS TO THE WAA S WINDS AND 850MB TEMPS RISING TO 0
TO -3C BY LATE AFTERNOON AS THE SFC HIGH OVER FAR SE ONTARIO
CONTINUES TO EXIT THE PICTURE. THE TRADITIONAL DOWNSLOPE LOCATIONS
OVER THE W HALF NEAR LAKE SUPERIOR SHOULD BE ABLE TO CLIMB INTO THE
MID TO UPPER 40S. A FEW 50F READINGS WILL NOT BE OUT OF THE
QUESTION.
OUR EYES WILL BE ON THE SFC LOW OVER THE DAKOTAS TUESDAY...AND THE S
LOW SHIFTING FROM CENTRAL KS TO W IA/MO BY THE END OF THE DAY.
TAKING A LOOK AT 500MB THE S SHORTWAVE OVER THE CENTRAL PLAINS
TUESDAY MORNING WILL CONTINUE TO STRENGTHEN. UNLIKE WHAT WE HAVE
SEEN FROM SYSTEMS RECENTLY...THIS ONE HAS SOME GOOD MOISTURE TO WORK
WITH...STREAMING N FROM THE W GULF OF MEXICO. THE NEARLY STACKED
SYSTEM WILL SWING ACROSS WI/W LOWER MI BY DAYBREAK
WEDNESDAY...PUSHING MIXED PRECIP ALONG THE WI BORDER BY 06Z
WEDNESDAY. DRY SOUNDINGS BELOW 800MB INDICATE THAT IT MAY TAKE A BIT
FOR THE NEAR-SFC LAYER TO MOISTEN ENOUGH FOR PRECIP TO FALL. EXPECT
MAINLY SNOW IF THE GFS IS CORRECT. THE 18Z AND 00Z GFS RUNS...WITH
THE MOST E TRACK OF THE SFC LOW...KEEPS ENOUGH COLD ENOUGH AIR
OVERHEAD TO KEEP MOST OF THE PRECIP STAYING AS SNOW EVEN ALONG THE
WI BORDER AND OUT E /ONLY A BIT OF FZRN AROUND MNM WEDNESDAY
MORNING/. THE QPF IS ON THE ORDER OF 0.1-0.2 IN LESS ON THE LATEST
RUN. THE NAM CONTINUES TO GO HIGH ON THE FZRN POTENTIAL. WHILE THE
18Z RUN OF THE NAM WAS A BIT COLDER/THE 00Z RUN HAS THE SFC LOW JUST
SLIGHTLY DEEPER AND TO THE W. HOWEVER...THE QPF HAS BEEN VERY
JUMPY...WITH RUN TO RUN CONSISTENCY ISSUES. WILL NOT GO COMPLETELY
WITH THE NAM OR GFS SOLUTIONS. THE SOLUTIONS DIVERGE AS EARLY AS
TUESDAY AFTERNOON OVER E KS/W MO...WITH THE NAM/ECMWF ON THE SLOW
SIDE COMPARED TO THE GFS. IT WILL BE INTERESTING TO SEE HOW THE
SOLUTIONS PAN OUT OVER THE NEXT DAY OR SO. WILL KEEP THE MENTION OF
SNOW AND MIXED PRECIP IN THE HWO...WITH SOME SLIGHT ADJUSTMENT. WILL
CONTINUE WITH MODERATE TO LOWER CONFIDENCE WITH THIS PERIOD.
WHILE THE S SFC LOW SHIFTS ACROSS E UPPER MI/N LOWER MI WEDNESDAY
AFTERNOON THE LOW THAT WAS IN THE DAKOTAS WILL SLIDE ACROSS N MN. SO
EVEN THOUGH THE INITIAL LOW SHIFTS ACROSS E ONTARIO AND INTO S
QUEBEC THURSDAY EVENING..LOW PRESSURE WILL LINGER ACROSS UPPER MI
THROUGH THE NIGHT AS THE SECONDARY LOW SHIFTS IN.
THE DGZ FINALLY FALLS WELL INTO THE MOISTURE LAYER OVERNIGHT
WEDNESDAY NIGHT THROUGH EARLY FRIDAY MORNING AS THIS SECONDARY LOW
SINKS ACROSS N LOWER MI THURSDAY MORNING. ALTHOUGH 850MB TEMPS FROM
THURSDAY AFTERNOON ON WILL BE -16C OR COLDER OVER THE W HALF...WINDS
LOOK TO BE SHIFTING QUITE A BIT...ANYWHERE OUT OF THE NW TO N TO NE.
THIS WILL LIMIT THE DEVELOPMENT OF STRONG LES BANDS. STILL...LES
WILL BE POSSIBLE. AN ADDITIONAL 2-5IN OF NEW SNOW WILL BE POSSIBLE
OVER THE LONGER PERIOD OF WEDNESDAY NIGHT THROUGH EARLY
FRIDAY...WITH THE HIGHEST AMOUNTS OVER THE FAVORABLE N WIND
SNOWBELTS.
LOOK FOR DRY WEATHER TO TAKE HOLD AGAIN FRIDAY AFTERNOON...WHEN THE
LARGE SFC HIGH SET UP FROM CENTRAL CANADA THROUGH MUCH OF THE
CENTRAL PLAINS EDGES INTO THE UPPER GREAT LAKES. THIS RIDGE OF HIGH
PRESSURE WILL REMAIN ACROSS UPPER MI INTO EARLY SATURDAY...BEFORE
EXITING TO THE SSE. GIVEN A MOSTLY CLEAR SKY AND ASSUMING NO
LINGERING LES...SATURDAY MORNING COULD BE PRETTY CHILLY IN THE
TRADITIONAL COLD SPOTS OF INTERIOR UPPER MI. DID ADJUST VALUES DOWN
SLIGHTLY FROM THE OVERALL MODEL BLEND.
LOW PRESSURE OVER MUCH OF CENTRAL CANADA ON SATURDAY WILL SWING A
TROUGH ACROSS ONTARIO SATURDAY NIGHT THROUGH SUNDAY. WHILE THE GFS
IS MORE PROGRESSIVE WITH THIS SYSTEM...THE ECMWF DEEPENS AN OFFSHOOT
OF THE MAIN LOW OVER ONTARIO AVERAGING 985MB. AT THIS POINT BOTH THE
ECMWF AND GFS PIN POINT THE E HALF OF UPPER MI TO GET 0.25IN OR MORE
OF LIQUID LATE SATURDAY NIGHT/EARLY SUNDAY MORNING. WITH 850MB TEMPS
OF -3 TO -5C A HEAVY WET SNOW IS MOST LIKELY. WILL HOLD OFF ON ANY
MENTION IN THE HWO QUITE YET...AS SEVERAL CHANGES WILL BE POSSIBLE
BETWEEN NOW AND THEN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1245 PM EDT MON MAR 23 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
DRIFTING S THRU ONTARIO WILL ALLOW VFR CONDITIONS TO CONTINUE AT
KIWD/KCMX/KSAW THRU THIS FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 510 AM EDT MON MAR 23 2015
HIGH PRES JUST NE OF LAKE SUPERIOR WILL DRIFT SOUTHEAST...REACHING
SOUTHERN ONTARIO BY TUE MORNING AND THE MID ATLANTIC STATES TUE
AFTN. WITH PRES GRADIENT REMAINING WEAK...WINDS WILL BE BLO 20KT
ACROSS LAKE SUPERIOR. A LOW PRESSURE SYSTEM OVER THE CENTRAL PLAINS
TUE WILL TRACK NE...CROSSING FAR NRN LWR MI WED AFTN. WINDS SHOULD
NOT STRENGTHEN MUCH AHEAD OF THIS FEATURE AS PRES GRADIENT DOES NOT
TIGHTEN SIGNIFICANTLY. STRONGEST WINDS WILL OCCUR THU AS HIGH PRES
BUILDS S TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO
THE UPPER LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...
AND IT`S NOT OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR
FOR A TIME. WINDS WILL THEN DIMINISH FRI AS A HIGH PRESSURE RIDGE
MOVES OVER THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS RALEIGH NC
257 PM EDT MON MAR 23 2015
.SYNOPSIS...A COOLER AND DRIER AIRMASS ASSOCIATED WITH A HIGH
PRESSURE SYSTEM TO THE NORTH WILL CONTROL THE PATTERN FOR MIDWEEK
BEFORE MORE UNSETTLED WEATHER ASSOCIATED WITH A LOW PRESSURE SYSTEM
AND ASSOCIATED COLD FRONT MOVE IN LATE WEEK..
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 245 PM MONDAY...
MUCH DRIER AIRMASS TO THE NORTH HAS MOVED IN AND HELPED TO SCOUR OUT
CLOUD COVER OVER THE NORTHWESTERN HALF OF THE CWA AND AS A RESULT
HAVE CAUSED TEMPERATURES TO RISE CONSIDERABLY ESPECIALLY IN THE
SOUTHWEST WHERE LOW 60S ARE NOW IN PLAY. CLOUDS HAVE CONTINUED TO
HANG ON IN THE EAST WHERE TEMPERATURES REMAIN COOLEST...PARTICULARLY
ALONG THE NORTHERN I-95 CORRIDOR. THIS PATTERN SHOULD PERSIST FOR
THE REST OF THE DAY AND WILL EXPECT TO SEE HIGHS IN THE MID 50S
NORTHEAST TO LOW 60S SOUTHWEST.
DRIER WEATHER IS EXPECTED OVERNIGHT AS WELL AND THE CHANCE FOR SOME
LOW CLOUDS IS DWINDLING ALTHOUGH RELATIVE HUMIDITY CROSS SECTIONS
AND RAP MODEL FORECASTS ARE SHOWING MOISTURE MOVING THROUGH THE NW
PIEDMONT DURING THE EARLY MORNING HOURS WHICH COULD HELP TO FORM
SOME BRIEF MVFR CEILINGS BUT CONFIDENCE IN THIS HAPPENING IS VERY
LOW AT THIS TIME. THUS WILL LOWER TEMPS A BIT INTO THE MID TO UPPER
30S FOR LOWS.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 245 PM MONDAY...
SURFACE HIGH PRESSURE OVER THE NORTHEAST WILL TRY TO WEDGE INTO THE
CAROLINAS BUT THE HIGH IS NOT PARTICULARLY STRONG OR IN AN IDEAL
POSITION FOR DAMMING...A LITTLE TOO FAR WEST. A SECONDARY HIGH WILL
TRY TO FORM ALONG THE DELMARVA LATER IN THE DAY AND THIS COULD
PRESENT MORE OF AN IN SITU DAMMING SCENARIO ON TUESDAY NIGHT AS
ISENTROPIC LIFT INCREASES ON THE 290K SURFACE. FLOW ALOFT WILL BE
FAIRLY ZONAL. THEREFORE LIGHT RAIN CHANCES INCREASE LATER TUESDAY
NIGHT...BUT OTHERWISE EXPECT A MOSTLY DRY FORECAST WITH PARTLY
CLOUDY SKIES. HIGHS IN THE MID 50S NORTHEAST TO MID 60S SOUTHWEST.
WINDS WILL VARY ACROSS THE CWA WITH A MORE SOUTHEASTERLY COMPONENT
OVER THE TRIAD AND A MORE NORTHEASTERLY COMPONENT IN THE NORTHEAST.
THUS PARTIALLY EXPLAINING THE DIFFERENCE IN FORECAST HIGHS AT AROUND
5 KTS. WITH THE INCREASE IN CLOUD COVER...HAVE INCREASED LOWS
TUESDAY NIGHT INTO THE LOW TO MIDDLE 40S NORTHEAST TO SOUTHWEST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...
GRADUAL MOISTURE ADVECTION TAKES PLACE WEDNESDAY INTO WEDNESDAY
NIGHT...WITH PRECIPITABLE WATER VALUES INCREASING WELL ABOVE NORMAL
BY 06Z THURSDAY. BUFR SOUNDINGS FROM BOTH THE NAM AND THE GFS
WEDNESDAY SUGGEST A SHARP INVERSION THROUGH THE MORNING WEDNESDAY
WITH MAINLY DRY AIR ABOVE...SUGGESTIVE OF THE POTENTIAL FOR DRIZZLE
WEDNESDAY MORNING AND POSSIBLY A PATCH OF LIGHT RAIN MAINLY OVER THE
WESTERN PIEDMONT WHERE THE LOW-LEVEL MOISTURE IS FORECAST JUST A
LITTLE DEEPER COMPARED TO THE REST OF THE AREA. BOTH THE NAM AND THE
GFS SUGGEST SOME LOW-LEVEL MOISTURE EROSION...SLOWEST IN THE
NORTHWEST PIEDMONT...AND WHILE BOTH THE NAM AND GFS SUGGEST SOME
CAPPING TO MODESTLY DEEP CONVECTION WEDNESDAY AFTERNOON...THE CAP
DOES ERODE ENOUGH TOWARD THE YADKIN RIVER THAT POSSIBLY A SHOWER
COULD OCCUR THERE AGAIN LATE IN THE DAY. HIGH TEMPERATURES HAVE
TRENDED WARMER BUT STILL EXPECT THE SAME PATTERN OF HIGHS
APPROACHING 60 TOWARD THE TRIAD AND NOTICEABLY WARMER TOWARD KFAY
AND KCTZ...AROUND 70 TO THE LOWER 70S.
WEDNESDAY NIGHT THERE IS GOOD VORTICITY ADVECTION AT 700MB ALONG
WITH INCREASING DIFFLUENCE IN MOISTURE ADVECTION. THE TIMING OF
DEEPENING MOISTURE DIFFERS ON THE NAM AND GFS BUFR SOUNDINGS...BUT
THEY ARE SIMILAR ENOUGH TO SUGGEST A GOOD CHANCE OF SHOWERS
DEVELOPING WEST-TO-EAST WEDNESDAY NIGHT...AND THESE CHANCES COULD
END UP BEING LIKELY OR EVEN CATEGORICAL AT SOME POINT PRIOR TO THEN.
CAPE IS VERY SKINNY ON BUFR SOUNDINGS BUT NON-ZERO...AND IF THE MID-
LEVEL WAVE AND DIFFLUENCE REMAIN AS FORECAST A RUMBLE OF THUNDER
CANNOT BE RULED OUT BUT WILL LEAVE OUT OF THE FORECAST FOR NOW.
TEMPERATURES SHOULD FALL LITTLE IN THE TRIAD...OVERALL THROUGHOUT
CENTRAL NORTH CAROLINA LOWS 55 TO 60.
THE SHORTWAVE MOVES OFF TO THE EAST THURSDAY EARLY AND THERE IS
FORECAST BY THE GFS A PERIOD OF CONVERGENCE ALOFT BEFORE THE COLD
FRONT GETS CLOSER LATER IN THE DAY. THE TIMING OF THE FRONTAL
PASSAGE IS A LITTLE SLOWER...AND THIS COULD RESULT IN GOOD WARMING
WITH SOME BREAKS IN THE CLOUDS FOR THE LATE MORNING INTO THE
AFTERNOON. GFS BUFR SOUNDINGS...IN FACT...SHOW THE POTENTIAL FOR A
GOOD BIT OF SUN ALONG AND EAST OF U.S. 1 FOR A TIME WHICH COULD HELP
TO ELEVATE TEMPERATURES FROM NEAR 80 TO 85 THERE. FOR THIS FORECAST
WILL HAVE MID 70S IN THE NORTHWEST PIEDMONT AND NEAR 80 IN THE
TRIANGLE...WITH SOLID LOWER 80S IN THE SOUTHEAST ZONES IN A MODESTLY
GUSTY SOUTHWEST WIND. IF THE FRONTAL TIMING SLOWS EVEN A LITTLE MORE
MUCH OF THURSDAY AFTERNOON COULD BE DRY...BUT FOR THIS FORECAST WILL
RETAIN CHANCES FOR SHOWERS AND A THUNDERSTORM THEN...LOW CHANCES
TOWARD INTERSTATE 95 AND HIGHER CHANCES TOWARD THE TRIAD. THURSDAY
COULD BE A DAY WITH MORNING SHOWERS MOVING EAST FOLLOWED BY A DECENT
BREAK IN PRECIPITATION CHANCES...WITH RENEWED CHANCES LATER IN THE
DAY COMING IN FROM THE NORTHWEST. INSTABILITY IS MARGINAL ON THE GFS
INTO THURSDAY EVENING...MLCAPE THROUGH THE LOWEST 2KM LESS THAN
500J/KG...BUT THE 0-3KM SHEAR IS GOOD APPROACHING 60KT WITH THE
FRONT. THE NAM IS MORE UNSTABLE...BUT JET SUPPORT SEEMS TO BE
LAGGING.
THE COLD FRONT WILL BE MOVING PAST CENTRAL NORTH CAROLINA THURSDAY
NIGHT WITH CHANCES FOR SHOWERS...AND POSSIBLY A THUNDERSTORM IN THE
EVENING AS COARSE MODEL SOUNDINGS FROM THE GFS AND ECMWF SUGGEST
STEEP ENOUGH LAPSE RATES TO CONTINUE THE CHANCE OF THUNDER INTO THE
EVENING. THE CAPE IS SKINNY...AND THOSE COARSE SOUNDINGS BECOME
STABLE OVERNIGHT BUT WITH ENOUGH MOISTURE TO SUGGEST THE POTENTIAL
FOR LINGERING SHOWERS INTO FRIDAY MORNING. SOME OF THE LATEST
GUIDANCE IS A LITTLE SLOWER WITH THE TIMING OF THE FRONTAL PASSAGE
AND THE CANADIAN AND DGEX ARE VERY SLOW...WHICH WOULD CARRY CHANCES
FOR PRECIPITATION THROUGH THE DAY FRIDAY. UNLESS THE FRONTAL TIMING
CONTINUES TO SLOW...THE MOST LIKELY SOLUTION CURRENTLY IS LINGERING
MORNING SHOWERS MOSTLY ALONG AND EAST OF U.S. 1...BUT FOR THIS
FORECAST WILL NOTE A SLIGHT CHANCE OF SHOWERS IN THE NORTHWEST
PIEDMONT THROUGHOUT FRIDAY AND CHANCES MAINLY ALONG AND EAST OF U.S.
1 DUE TO UNCERTAINTY. AS THE UPPER TROUGH AXIS APPROACHES...
CONSIDERING THE SLOWEST SOLUTIONS THEN A LINGERING SHOWER COULD
CONTINUE IN THE EVENING MAINLY ALONG AND EAST OF INTERSTATE 95...
BUT IF THE LATEST GFS VERIFIES WITH K INDICES FALLING GREATLY...
CHANCES FOR PRECIPITATION WILL END EARLIER THAN FORECAST.
THE BIGGEST CHANGES FROM MODEL GUIDANCE OF SUNDAY IS OVERALL DRIER
FROM SATURDAY THROUGH THE WEEKEND. THE DEEP TROUGH AXIS MOVES
THROUGH THE EASTERN CONUS FRIDAY AND SATURDAY WITH SOME DIFFERENCES
IN THE DETAILS ON THE GFS AND THE ECMWF...BUT BOTH MODELS ARE DRIER
WITH REGARD TO THE MEAN MOISTURE AND WITH SURFACE LOW PRESSURE
FARTHER OFFSHORE. WHILE TEMPERATURES WILL BE BELOW NORMAL...QPF HAS
TRENDED TO VERY LIGHT OR NIL AND PLANNING NOW TO FEATURE A DRY
FORECAST FOR CENTRAL NORTH CAROLINA AFTER EARLY FRIDAY NIGHT.
THE SURFACE RIDGE AXIS SHOULD MOVE QUICKLY SOUTH BY SUNDAY...MAKING
FOR A RETURN TO A SOUTHWEST FLOW AND WARMER TEMPERATURES. SURFACE
RIDGING IS FORECAST ACROSS THE GULF...WHICH SHOULD LIMIT MOISTURE
RETURN IN ADVANCE OF ANOTHER COLD FRONT...FORECAST TO MOVE THROUGH
CENTRAL NORTH CAROLINA MONDAY. THE ECMWF IS DEEPER WITH THE MID-
LEVEL WAVE MOVING THROUGH THE REGION...WHILE THE GFS HAS A FLATTER
FLOW. IF THE ECMWF VERIFIES WITH ITS STRONGER MID-LEVEL WAVE...THERE
COULD BE SOME PATCHES OF LIGHT RAIN OR SPRINKLES PRECEDING THE
FRONT. FOR NOW...WILL OPT TO SHOW JUST AN INCREASE IN CLOUDS
OVERNIGHT SUNDAY THROUGH ABOUT THE FIRST HALF OF MONDAY AND LEAVE
OUT PRECIPITATION ON THE SEVENTH DAY. IF IT WOULD OCCUR...IT SHOULD
BE LIGHT AS BOTH THE GFS AND ECMWF DIMINISH THE AMOUNT OF MOISTURE
AHEAD OF THE FRONT AS IT HEADS SOUTH TOWARD CENTRAL NORTH CAROLINA.
THE TIGHTEST SURFACE GRADIENTS DURING THE PERIOD ARE LATE THURSDAY
AFTERNOON AND EVENING...EARLY SATURDAY...AND THEN SUNDAY WHEN A
LITTLE MORE IN THE WAY OF GUSTS SHOULD BE OBSERVED. TEMPERATURES IN
THE LATTER PART OF THE LONG-TERM PERIOD WILL AVERAGE BELOW THE
NORMALS OF AROUND 65 TO 70 FOR LATE MARCH. COOLEST DAY SHOULD BE
SATURDAY WITH THE LOWEST 1000-850MB THICKNESSES SUGGESTIVE OF ONLY
THE MID 40S IN THE TRIAD. WILL LEAN A CATEGORY ABOVE THAT AND CLOSER
TO THE MOS CONSENSUS...APPROACHING 50 IN THE IMMEDIATE TRIAD AND FAR
NORTHWEST PIEDMONT AND 50 TO 55 ELSEWHERE. SATURDAY NIGHT COULD
FEATURE SOME UPPER 20S FOR LOWS IF CLOUDS DIMINISH AS EXPECTED.
GRADUAL WARMING TREND THROUGH THE WEEKEND...EXPECTING HIGHS AROUND
NORMAL BY MONDAY.
&&
.AVIATION /12Z MONDAY THROUGH SATURDAY/...
AS OF 145 PM MONDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS ARE PREVAILING OVER THE AREA AS
DRIER AIR HAS MOVED IN AND CLOUDS HAVE SCATTERED OUT. WIND GUSTS
WILL CONTINUE THIS AFTERNOON MAINLY OUT OF THE EAST OR NORTHEAST AT
15-20 KTS. LATER IN THE AFTERNOON THESE GUSTS COULD BEGIN TO SUBSIDE
AS HIGH PRESSURE MOVES CLOSER. OUT IN THE TRIAD WINDS WILL QUICKLY
SWING AROUND TO A MORE SOUTHEASTERLY DIRECTION AND SHOULD REMAIN
THAT WAY THROUGH THE REST OF THE PERIOD. OVERNIGHT TONIGHT THERE ARE
SOME HINTS OF SOME LOW LEVEL MOISTURE MOVING INTO THE TRIAD AREA
WHICH COULD GIVE SOME BRIEF MVFR CEILINGS BUT OTHERWISE NOTHING
SIGNIFICANT AS FAR AS CEILING OR VISIBILITY RESTRICTIONS. MOSTLY
SCATTERED CLOUDS FOR TUESDAY WITH THE POSSIBILITY OF LOWER CEILINGS
EARLY IN THE DAY IN THE NORTHWEST. EASTERLY WINDS WILL PREVAIL FOR
MUCH OF THE DAY TOMORROW WITH MORE SOUTHEASTERLY WINDS IN THE TRIAD.
LONG TERM: FOG/LOW STRATUS WILL BE POSSIBLE WEDNESDAY MORNING. A
MOIST CONVECTIVE RETURN FLOW REGIME MOVES IN WEDNESDAY NIGHT AND
COULD KEEP WEATHER UNSETTLED THROUGH FRIDAY AS A COLD FRONT CROSSES
THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...DJF
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
132 PM EDT MON MAR 23 2015
.SYNOPSIS...
A SERIES OF WEAK AREAS OF LOW PRESSURE WILL MOVE EAST ALONG A
STALLED FRONT SOUTH OF THE AREA THROUGH TUESDAY. HIGH PRESSURE
WILL EXTEND INTO THE AREA FROM THE NORTH THROUGH MIDWEEK. A STRONG
COLD FRONT WILL APPROACH FROM THE WEST THURSDAY AND MOVE THROUGH
FRIDAY. LOW PRESSURE WILL MOVE ACROSS SOUTHEAST OF THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1230 PM MONDAY...NO SIGNIF CHANGES TO PREV FCST WITH SMALL
POP IMD CST GRAD ENDING LATER TODAY. PLENTY OF CLOUDS WILL CONT
WITH COOL HIGHS IN UPR 40S NE TO MID/UPR 50S SW. GUSTY NE WINDS
WL CONT ALONG THE BEACHES.
PREV DISC...BULK OF THE PRECIPITATION NOW OFFSHORE WITH JUST SOME
LIGHT RAIN SKIRTING THE IMMEDIATE COAST. SURFACE OBSERVATION
INDICATE THE LIGHT RETURNS INLAND STILL NOT REACHING THE GROUND.
PER THE LATEST RUN OF THE 3KM HRRR MODEL...HAVE SCALED POPS BACK
TO CHANCE...WITH 40 PCT ALONG THE SOUTHERN COAST TAPERING BACK TO
SLIGHT CHANCE OVER THE FAR NORTHWESTERN COUNTIES. ADDITIONAL
SHORTWAVE ENERGY COULD PRODUCE A FEW LIGHT SHOWERS THROUGH
MIDDAY...BUT GUIDANCE ALL SHOWS DRIER AIR FILTERING IN AFTER NOON
WITH DEWPOINTS DROPING BACK INTO THE 30S. IT WILL BE A CHILLY
START TO THE WORKWEEK WITH HIGHS TEMPERATURES LINGERING IN THE
UPPER 40S OVER THE NORTHERN OUTER BANKS WITH LOW/MID 50S
ELSEWHERE...EXCEPT A FEW UPPER 50S OVER THE FAR SOUTHWESTERN
COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 330 AM MONDAY...LOW PRESSURE WILL MOVE WELL EAST OF THE AREA
TONIGHT AS COOL HIGH PRESSURE BUILDS SOUTH FROM CANADA. EXPECT A
VEIL OF MID CLOUDS TO HANG AROUND...BUT TEMPERATURES WILL STILL BE
CHILLY FOR LATE MARCH WITH LOWS RANGING IN THE MID/UPPER 30S
INLAND TO THE LOWER 40S OUTER BANKS.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
AS OF 330 AM MON...LONG TERM PERIOD WILL FEATURE VERY
CHANGEABLE WEATHER PATTERN TYPICAL OF EARLY SPRING WITH LARGE
VARIATION IN TEMPERATURES AND AN UNSETTLED PATTERN.
MAINLY DRY CONDITIONS TUE NIGHT INTO WED WITH HIGH PRES TO THE
NORTHEAST REESTABLISHING ITSELF ACROSS E NC WITH ZONAL FLOW ALOFT.
SOME MODERATION IN TEMPS FOR TUE THOUGH STILL BELOW CLIMO WITH HIGHS
NEAR 50 NORTHEAST TO NEAR 60 SOUTHWEST UNDER PARTLY SUNNY SKIES.
LOWS NEAR CLIMO TUE NIGHT WITH READINGS IN THE 40S. CONTINUED
PREVIOUS FCST TREND WITH PCPN HOLDING OFF DURING THE DAY WED AS
RETURN FLOW BECOMES SOUTHEAST LATE IN THE DAY THOUGH LOW LEVELS
STILL DRY WITH JUST AN INC IN CLOUD COVER EXPECTED. HIGHS EXPECTED
NEAR 70 AWAY FROM THE COAST WITH 50S ON THE OUTER BANKS WITH
CONTINUED NORTHEAST BREEZE KEEPING IT COOLER HERE.
INC CHANCES FOR RAIN SHOWERS WED NIGHT AS RETURN SSW FLOW
STRENGTHENS AND RAPID INC IN LOW LEVEL MOISTURE ENSUES. SHORTWAVE
ENERGY PIVOTING AROUND LONG WAVE CENTRAL CONUS TROUGH WILL AID IN
UPR SUPPORT FOR SCT TO NUMEROUS RAIN SHOWERS.
FOR THUR...WARM AND HUMID DAY EXPECTED WITH BUILDING LOW LEVEL
THICKNESSES AND RESPONDING INC TEMPS AND DEWPOINTS EXPECTED AHEAD OF
APPROACHING STRONG COLD FRONT AND AFOREMENTIONED LONG WAVE TROUGH.
SFC INSTABILITY WILL BE PRESENT WITH PARTLY SUNNY SKIES EXPECTED
ALONG WITH SUFFICIENT DEEP LAYER SHEAR FOR THE POSSIBILITY OF
ORGANIZED THUNDER. HOWEVER...UPR SUPPORT WILL REMAIN WELL WEST OF
THE AREA AS POSITIVELY TILTED TROUGH IS SLOW TO MAKE HEADWAY
TOWARDS E NC...SO THREAT FOR SEVERE IS MARGINAL AT THIS TIME.
HIGHS WILL EASILY CLIMB INTO THE 70S...POSSIBLY HIGHER IF MORE
SUNSHINE BREAKS OUT. PRECIP THREAT WILL CONTINUE INTO THUR NIGHT
AS 23/00Z GFS/ECM/CMC IN GENERAL AGREEMENT ON A THUR NIGHT/FRI
MORNING FRONTAL PASSAGE.
FOR FRIDAY...POSITIVELY TILTED UPR TROUGH REMAINS WEST OF THE AREA
DESPITE THE SFC FRONTAL PASSAGE. MODELS INDICATE MORE SHORTWAVE
ENERGY ALOFT PRODUCING CHANCES FOR PRECIP THROUGH THE DAY AND WILL
RETAIN THE CHANCE POPS. TEMPS WILL BE NEAR CLIMO WITH HIGHS
GENERALLY IN THE 60S...WITH COOLER 50S OBX UNDER NORTHEAST SFC FLOW.
FRI NIGHT THROUGH SAT THERE IS DISAGREEMENT WITH RESPECT TO UPR
SUPPORT AS TROUGH AXIS WORKS THROUGH E NC. DETERMINISTIC GFS/CMC
CONTINUE WITH A WETTER SOLN WITH A COLD RAIN POSSIBLY MIXING WITH A
FEW SNOW SHOWERS...THOUGH LATEST 23/00Z ECMWF HAS A DRIER TREND.
WILL CONTINUE PREVIOUS CHANCE POPS AS WOULD LIKE TO SEE MORE
CONSISTENCY FROM ECMWF BEFORE MAKING LARGE SCALE CHANGES.
SUNDAY WILL BE QUITE COLD FOR LATE MARCH WITH TEMPS SOME 15-20
DEGREES BELOW CLIMO AND POSSIBLE FROST OR FREEZING CONDITIONS FOR E
NC. GROWING SEASON WILL BEGIN ACROSS ALL OF EASTERN NC ON MARCH 28.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 18Z TUESDAY/...VFR CONDITIONS EXPECTED
THROUGH THE TAF PERIOD WITH A COASTAL LOW EXITING TO THE SOUTHEAST
WHILE SFC HIGH PRESSURE BUILDS IN FROM THE NORTH. THIS CREATES A
GRADIENT CONDUCIVE FOR GUSTY NE WINDS ACROSS ALL TAF SITES THROUGH
THE AFTERNOON. CLOUDS WILL CONTINUES TO ERODE FROM WEST TO EAST
THROUGH THE AFTERNOON. CLOUDS WILL BUILD BACK IN HOWEVER THROUGH
THE EARLY MORNING HOURS TUESDAY AS A MID LEVEL IMPULSE MOVES
NORTH OF THE AREA. NE WINDS DIMINISH OVERNIGHT BUT INCREASE A BIT
AFTER SUNRISE. SCT/BKN CLOUDS CAN BE EXPECTED THROUGH THE DAY
TUESDAY.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...VFR CONDITIONS WILL DOMINATE TUE AND WED. NEXT
CHANCE FOR RAIN SHOWERS AND SUB VFR CONDITIONS WILL BE WED NIGHT
INTO THUR AS MOISTURE STREAMS NORTHWARD AHEAD OF STRONG COLD FRONT
SET TO PASS THROUGH BY FRIDAY MORNING. S TO SW WINDS WILL BE GUSTY
ON THURSDAY.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1230 PM MONDAY...NO CHANGES AS WINDS HAVE INCREASED AS
EXPECTED ALONG CST. SCA WILL CONT THRU AFTN FOR ALL BUT WRN
RIVERS.
PREV DISC...WINDS HAVE STARTED TO INCREASE ON THE SOUNDS AND
NORTHERN WATERS OVER THE PAST COUPLE OF HOURS. THE GRADIENT WILL
INCREASE DRAMATICALLY OVER THE NEXT FEW HOURS BETWEEN LOW PRESSURE
PASSING TO OUR SOUTH AND CANADIAN HIGH PRESSURE BUILDING DOWN FROM
THE NORTH. EXPECT NORTHEAST WINDS TO INCREASE TO 20 TO 25 KNOTS
OVER THE COASTAL WATERS WITH A PERIOD OF 25 TO 30 KNOT WINDS
POSSIBLE OVER PORTIONS OF THE CENTRAL WATERS THROUGH THE MID TO
LATE MORNING HOURS. ON THE SOUNDS...WINDS WILL GENERALLY BE 15 TO
25 KNOTS WITH A FEW GUSTS TO 30 KNOTS POSSIBLE THIS MORNING
ESPECIALLY. PER LATEST LOCAL NWPS/SWAN MODEL...SEAS WILL BUILD TO
AS HIGH AS 7 OR 8 FEET THROUGH THE LATE MORNING AND AFTERNOON
HOURS...ESPECIALLY CENTRAL AND NORTHERN WATERS. ONLY CHANGE TO
ADVISORIES WAS TO EXTEND FAR SOUTHERN WATERS INTO TUESDAY EVENING
WITH SEAS REMAINING ELEVATED.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...THE PRESSURE GRADIENT LOOSENS ON TUE
WITH SCA CONDITIONS ENDING. HIGH PRESSURE WILL CONTINUE TO PRODUCE
NORTHEAST WINDS IN THE 15-20 KT RANGE THROUGH TUE NIGHT. THE HIGH
WILL MOVE OFF THE COAST ON WEDNESDAY AND WINDS WILL VEER TO
SOUTHEAST LATE IN THE AFTERNOON. THE FLOW WILL CONTINUE TO VEER TO
SOUTH WEDNESDAY NIGHT AND THURSDAY AS THE HIGH MOVES EAST AND A COLD
FRONT APPROACHES FROM THE WEST. SCA CONDITIONS WILL LIKELY REDEVELOP
BY LATE WED NIGHT OR THURSDAY AS SOUTHERLY WINDS STRENGTHEN AND SEAS
BUILD ABOVE 6 FT. FRONT WILL PASS OFF THE COAST FRI MORNING WITH
WINDS TURNING NORTHERLY. THE NORTH WINDS WILL STRENGTHEN ON SATURDAY
AS STRONG COLD AIR ADVECTION MOVES INTO THE E NC WATERS WITH GUSTY
NORTH WINDS AND HIGH SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR AMZ130-
131.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...RF/CTC
SHORT TERM...CTC
LONG TERM...TL
AVIATION...TL/LEP
MARINE...RF/CTC/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1231 PM EDT MON MAR 23 2015
.SYNOPSIS...
A SERIES OF WEAK AREAS OF LOW PRESSURE WILL MOVE EAST ALONG A
STALLED FRONT SOUTH OF THE AREA THROUGH TUESDAY. HIGH PRESSURE
WILL EXTEND INTO THE AREA FROM THE NORTH THROUGH MIDWEEK. A STRONG
COLD FRONT WILL APPROACH FROM THE WEST THURSDAY AND MOVE THROUGH
FRIDAY. LOW PRESSURE WILL MOVE ACROSS SOUTHEAST OF THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1230 PM MONDAY...NO SIGNIF CHANGES TO PREV FCST WITH SMALL
POP IMD CST GRAD ENDING LATER TODAY. PLENTY OF CLOUDS WILL CONT
WITH COOL HIGHS IN UPR 40S NE TO MID/UPR 50S SW. GUSTY NE WINDS
WL CONT ALONG THE BEACHES.
PREV DISC...BULK OF THE PRECIPITATION NOW OFFSHORE WITH JUST SOME
LIGHT RAIN SKIRTING THE IMMEDIATE COAST. SURFACE OBSERVATION
INDICATE THE LIGHT RETURNS INLAND STILL NOT REACHING THE GROUND.
PER THE LATEST RUN OF THE 3KM HRRR MODEL...HAVE SCALED POPS BACK
TO CHANCE...WITH 40 PCT ALONG THE SOUTHERN COAST TAPERING BACK TO
SLIGHT CHANCE OVER THE FAR NORTHWESTERN COUNTIES. ADDITIONAL
SHORTWAVE ENERGY COULD PRODUCE A FEW LIGHT SHOWERS THROUGH
MIDDAY...BUT GUIDANCE ALL SHOWS DRIER AIR FILTERING IN AFTER NOON
WITH DEWPOINTS DROPING BACK INTO THE 30S. IT WILL BE A CHILLY
START TO THE WORKWEEK WITH HIGHS TEMPERATURES LINGERING IN THE
UPPER 40S OVER THE NORTHERN OUTER BANKS WITH LOW/MID 50S
ELSEWHERE...EXCEPT A FEW UPPER 50S OVER THE FAR SOUTHWESTERN
COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 330 AM MONDAY...LOW PRESSURE WILL MOVE WELL EAST OF THE AREA
TONIGHT AS COOL HIGH PRESSURE BUILDS SOUTH FROM CANADA. EXPECT A
VEIL OF MID CLOUDS TO HANG AROUND...BUT TEMPERATURES WILL STILL BE
CHILLY FOR LATE MARCH WITH LOWS RANGING IN THE MID/UPPER 30S
INLAND TO THE LOWER 40S OUTER BANKS.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
AS OF 330 AM MON...LONG TERM PERIOD WILL FEATURE VERY
CHANGEABLE WEATHER PATTERN TYPICAL OF EARLY SPRING WITH LARGE
VARIATION IN TEMPERATURES AND AN UNSETTLED PATTERN.
MAINLY DRY CONDITIONS TUE NIGHT INTO WED WITH HIGH PRES TO THE
NORTHEAST REESTABLISHING ITSELF ACROSS E NC WITH ZONAL FLOW ALOFT.
SOME MODERATION IN TEMPS FOR TUE THOUGH STILL BELOW CLIMO WITH HIGHS
NEAR 50 NORTHEAST TO NEAR 60 SOUTHWEST UNDER PARTLY SUNNY SKIES.
LOWS NEAR CLIMO TUE NIGHT WITH READINGS IN THE 40S. CONTINUED
PREVIOUS FCST TREND WITH PCPN HOLDING OFF DURING THE DAY WED AS
RETURN FLOW BECOMES SOUTHEAST LATE IN THE DAY THOUGH LOW LEVELS
STILL DRY WITH JUST AN INC IN CLOUD COVER EXPECTED. HIGHS EXPECTED
NEAR 70 AWAY FROM THE COAST WITH 50S ON THE OUTER BANKS WITH
CONTINUED NORTHEAST BREEZE KEEPING IT COOLER HERE.
INC CHANCES FOR RAIN SHOWERS WED NIGHT AS RETURN SSW FLOW
STRENGTHENS AND RAPID INC IN LOW LEVEL MOISTURE ENSUES. SHORTWAVE
ENERGY PIVOTING AROUND LONG WAVE CENTRAL CONUS TROUGH WILL AID IN
UPR SUPPORT FOR SCT TO NUMEROUS RAIN SHOWERS.
FOR THUR...WARM AND HUMID DAY EXPECTED WITH BUILDING LOW LEVEL
THICKNESSES AND RESPONDING INC TEMPS AND DEWPOINTS EXPECTED AHEAD OF
APPROACHING STRONG COLD FRONT AND AFOREMENTIONED LONG WAVE TROUGH.
SFC INSTABILITY WILL BE PRESENT WITH PARTLY SUNNY SKIES EXPECTED
ALONG WITH SUFFICIENT DEEP LAYER SHEAR FOR THE POSSIBILITY OF
ORGANIZED THUNDER. HOWEVER...UPR SUPPORT WILL REMAIN WELL WEST OF
THE AREA AS POSTITVELY TILTED TROUGH IS SLOW TO MAKE HEADWAY TOWARDS
E NC...SO THREAT FOR SEVERE IS MARGINAL AT THIS TIME. HIGHS WILL
EASILY CLIMB INTO THE 70S...POSSIBLY HIGHER IF MORE SUNSHINE BREAKS
OUT. PRECIP THREAT WILL CONTINUE INTO THUR NIGHT AS 23/00Z
GFS/ECM/CMC IN GENERAL AGREEMENT ON A THUR NIGHT/FRI MORNING FRONTAL
PASSAGE.
FOR FRIDAY...POSITIVELY TILTED UPR TROUGH REMAINS WEST OF THE AREA
DESPITE THE SFC FRONTAL PASSAGE. MODELS INDICATE MORE SHORTWAVE
ENERGY ALOFT PRODUCING CHANCES FOR PRECIP THROUGH THE DAY AND WILL
RETAIN THE CHANCE POPS. TEMPS WILL BE NEAR CLIMO WITH HIGHS
GENERALLY IN THE 60S...WITH COOLER 50S OBX UNDER NORTHEAST SFC FLOW.
FRI NIGHT THROUGH SAT THERE IS DISAGREEMENT WITH RESPECT TO UPR
SUPPORT AS TROUGH AXIS WORKS THROUGH E NC. DETERMINISTIC GFS/CMC
CONTINUE WITH A WETTER SOLN WITH A COLD RAIN POSSIBLY MIXING WITH A
FEW SNOW SHOWERS...THOUGH LATEST 23/00Z ECMWF HAS A DRIER TREND.
WILL CONTINUE PREVIOUS CHANCE POPS AS WOULD LIKE TO SEE MORE
CONSISTENCY FROM ECMWF BEFORE MAKING LARGE SCALE CHANGES.
SUNDAY WILL BE QUITE COLD FOR LATE MARCH WITH TEMPS SOME 15-20
DEGREES BELOW CLIMO AND POSSIBLE FROST OR FREEZING CONDITIONS FOR E
NC. GROWING SEASON WILL BEGIN ACROSS ALL OF EASTERN NC ON MARCH 28.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 12Z TUESDAY/...A GENERALLY DRY SUB CLOUD LAYER
HAS PREVENTED CEILINGS FROM DROPPING DESPITE SOME LIGHT
PRECIPITATION RETURNS ON RADAR. THE BULK OF THE LIGHT RAIN HAS
OCCURRED ALONG THE SOUTHERN COAST. CEILINGS ARE CURRENTLY MVFR AT
KISO...BUT ANTICIPATE ALL CEILINGS TO BE VFR BY 15Z OR SO AS
DEWPOINTS DROP INTO THE 30S. EXPECT VFR CONDITIONS OVERNIGHT AS
DRY COOL HIGH PRESSURE SETTLES SOUTH.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...VFR CONDITIONS WILL DOMINATE TUE AND WED. NEXT
CHANCE FOR RAIN SHOWERS AND SUB VFR CONDITIONS WILL BE WED NIGHT
INTO THUR AS MOISTURE STREAMS NORTHWARD AHEAD OF STRONG COLD FRONT
SET TO PASS THROUGH BY FRIDAY MORNING. S TO SW WINDS WILL BE GUSTY
ON THURSDAY.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1230 PM MONDAY...NO CHANGES AS WINDS HAVE INCREASED AS
EXPECTED ALONG CST. SCA WILL CONT THRU AFTN FOR ALL BUT WRN
RIVERS.
PREV DISC...WINDS HAVE STARTED TO INCREASE ON THE SOUNDS AND
NORTHERN WATERS OVER THE PAST COUPLE OF HOURS. THE GRADIENT WILL
INCREASE DRAMATICALLY OVER THE NEXT FEW HOURS BETWEEN LOW PRESSURE
PASSING TO OUR SOUTH AND CANADIAN HIGH PRESSURE BUILDING DOWN FROM
THE NORTH. EXPECT NORTHEAST WINDS TO INCREASE TO 20 TO 25 KNOTS
OVER THE COASTAL WATERS WITH A PERIOD OF 25 TO 30 KNOT WINDS
POSSIBLE OVER PORTIONS OF THE CENTRAL WATERS THROUGH THE MID TO
LATE MORNING HOURS. ON THE SOUNDS...WINDS WILL GENERALLY BE 15 TO
25 KNOTS WITH A FEW GUSTS TO 30 KNOTS POSSIBLE THIS MORNING
ESPECIALLY. PER LATEST LOCAL NWPS/SWAN MODEL...SEAS WILL BUILD TO
AS HIGH AS 7 OR 8 FEET THROUGH THE LATE MORNING AND AFTERNOON
HOURS...ESPECIALLY CENTRAL AND NORTHERN WATERS. ONLY CHANGE TO
ADVISORIES WAS TO EXTEND FAR SOUTHERN WATERS INTO TUESDAY EVENING
WITH SEAS REMAINING ELEVATED.
LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 AM MON...THE PRESSURE GRADIENT LOOSENS ON TUE
WITH SCA CONDITIONS ENDING. HIGH PRESSURE WILL CONTINUE TO PRODUCE
NORTHEAST WINDS IN THE 15-20 KT RANGE THROUGH TUE NIGHT. THE HIGH
WILL MOVE OFF THE COAST ON WEDNESDAY AND WINDS WILL VEER TO
SOUTHEAST LATE IN THE AFTERNOON. THE FLOW WILL CONTINUE TO VEER TO
SOUTH WEDNESDAY NIGHT AND THURSDAY AS THE HIGH MOVES EAST AND A COLD
FRONT APPROACHES FROM THE WEST. SCA CONDITIONS WILL LIKELY REDEVELOP
BY LATE WED NIGHT OR THURSDAY AS SOUTHERLY WINDS STRENGTHEN AND SEAS
BUILD ABOVE 6 FT. FRONT WILL PASS OFF THE COAST FRI MORNING WITH
WINDS TURNING NORTHERLY. THE NORTH WINDS WILL STRENGTHEN ON SATURDAY
AS STRONG COLD AIR ADVECTION MOVES INTO THE E NC WATERS WITH GUSTY
NORTH WINDS AND HIGH SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR AMZ130-
131.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...RF/CTC
SHORT TERM...CTC
LONG TERM...TL
AVIATION...CTC/TL
MARINE...RF/CTC/TL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1240 PM CDT MON MAR 23 2015
.UPDATE...
ISSUED AT 1241 PM CDT MON MAR 23 2015
LATEST SATELLITE ANALYSIS SHOWS STRATUS BEGINNING TO DISSIPATE
OVER NORTHWEST AND CENTRAL NORTH DAKOTA. THUS NO SIGNIFICANT
CHANGES TO SKY COVER...JUST A GENERAL DECREASE IN CLOUDS THROUGH
THE AFTERNOON. WE WILL SEE INCREASING HIGH CLOUDS THROUGH THE
AFTERNOON OVER THE SOUTHWEST AHEAD OF THE NEXT APPROACHING SYSTEM.
DID BUMP DOWN TEMPERATURES A BIT DUE TO THE SLOW START TODAY WITH
THE STRATUS.
UPDATE ISSUED AT 1036 AM CDT MON MAR 23 2015
MAIN ISSUE FOR THE MORNING UPDATE WILL BE SKY COVER...AND ITS
POSSIBLE AFFECTS ON HIGH TEMPERATURES.
SURFACE LOW NOTED ALONG THE CANADIAN BORDER NORTH OF MINOT WITH A
COLD FRONT EXTENDING THROUGH SOUTHWEST NORTH DAKOTA. BEHIND THE
FRONT MVFR STRATUS HAS FILLED IN OVER THE NORTHWEST AND NORTH
CENTRAL. AHEAD OF THE FRONT...ANOTHER AREA OF MVFR TO IFR STRATUS
REMAINS OVER THE JAMES RIVER VALLEY AND INTO EASTERN NORTH DAKOTA.
LATEST HRRR INDICATES STRATUS HOLDING ON OVER THE NORTHWEST AND
CENTRAL NORTH DAKOTA THROUGH LATE MORNING...THEN QUICKLY ERODING
IN THE EARLY AFTERNOON. THE STRATUS IN THE JAMES RIVER VALLEY
NORTH INTO THE TURTLE MOUNTAINS AREA...HANGS ON THROUGH MUCH OF
THE AFTERNOON. CURRENT FORECAST HIGHS ARE LOWEST IN THESE
AREAS...SO NOT CONFIDENT ON HOW MUCH/IF ANY THESE NEED TO BE
DROPPED. THE CLOUDS OVER THE SOUTHWEST WHERE WARMEST TEMPERATURES
ARE EXPECTED...SHOULD DIMINISH QUICKLY LATE MORNING THROUGH EARLY
AFTERNOON. THUS HIGHS HERE MIGHT ALSO BE OKAY. WILL HOPEFULLY GET
A BETTER IDEA ON TEMPERATURES WITH THE LATE MORNING/EARLY
AFTERNOON UPDATE.
UPDATE ISSUED AT 641 AM CDT MON MAR 23 2015
EARLY MORNING 11-3.9 MICRON SATELLITE IMAGERY SHOWS AREAS OF
STRATUS FROM SOUTHERN SASKATCHEWAN INTO NORTHERN AND EASTERN NORTH
DAKOTA. THE STRATUS IS EXPECTED TO GRADUALLY DIMINISH
TODAY...THOUGH IT COULD BE SLOW TO LEAVE IN THE EAST WHERE THE LOW
LEVEL RELATIVE HUMIDITY VALUES PERSIST INTO EARLY AFTERNOON
ACCORDING TO THE 23.06Z NAM. WILL NOT ALTER HIGHS AT THE
MOMENT...BUT IT IS SOMETHING TO WATCH IF THE STRATUS PERSISTS
LONGER THAN EXPECTED. HELD ONTO PATCHY FOG THIS MORNING WITH A
COUPLE SPOTS ACROSS THE FORECAST AREA REPORTING SMALL REDUCTIONS
IN VISIBILITY. OVERALL...MADE ONLY MINOR CHANGES TO BLEND IN
CURRENT CONDITIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CDT MON MAR 23 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE LOW CLOUDS
THIS MORNING FAR NORTH AND SOUTH CENTRAL/SOUTHEAST...THEN
INCREASING CHANCES FOR RAIN TONIGHT WEST AND SOUTH
CENTRAL...ALONG WITH A THREAT FOR FREEZING RAIN FAR NORTHWEST.
CURRENTLY...NORTHWEST FLOW ALOFT WITH A POTENT S/WV TROUGH MOVING
EAST-SOUTHEAST INTO NORTHWESTERN MINNESOTA. SNOW CONTINUES OVER
NORTHEASTERN NORTH DAKOTA...GRAZING THE TURTLE MOUNTAIN AREA.
ELSEWHERE...MOSTLY CLEAR SOUTHWEST WITH CLOUDY SKIES FAR NORTH AND
SOUTH CENTRAL WITH LOW STRATUS. WILL LEAVE PATCHY FOG IN THE
FORECAST WITH THIS ISSUANCE AS STILL POTENTIAL FOR DEVELOPMENT
THIS MORNING.
BECOMING MOSTLY SUNNY TODAY AS LOW CLOUDS BURN OFF LATER THIS
MORNING. POSSIBLE THAT WE WILL HAVE SOME LINGERING LOW CLOUDS
ACROSS THE SOUTHEAST AND FAR NORTH...WHICH WOULD IMPACT DAYTIME
HIGHS. STRONG WAA ACROSS THE SOUTHWEST WILL SEE DAYTIME HIGHS
CLIMB WELL INTO THE 50S ALONG TO SOUTH AND WEST OF THE MISSOURI
RIVER...WITH LOW 60S PROBABLE SOUTHWEST. MODELS GENERATING DIURNAL
INSTABILITY WITH CAPE CLIMBING INTO THE HUNDREDS OVER
SOUTHEASTERN MONTANA THIS AFTERNOON. DO NOT EXPECT ANY CONVECTIVE
ACTIVITY OVER MY AREA...BUT WOULD NOT BE SURPRISED IF A FEW
LIGHTNING STRIKES POPPED UP OFF TO OUR SOUTHWEST.
UPPER LEVEL TROUGH MOVES ACROSS THE ROCKIES TONIGHT INTO THE
NORTHERN HIGH PLAINS. ASSOCIATED SFC TROUGH IN RESPONSE MOVES INTO
THE WESTERN DAKOTAS. INCREASING CHANCES FOR RAIN FAR WEST THIS
EVENING...FOLLOWED BY INCREASING CHANCES FOR RAIN WEST AND SOUTH
CENTRAL OVERNIGHT. THERE LOOKS TO BE A THREAT FOR FREEZING RAIN
ACROSS MY NORTHWEST TONIGHT IF AIR TEMPERATURES COOL TO BELOW 32F
AS MODELS SUGGEST. THIS WILL BE MENTIONED IN BOTH THE HWO AND SPS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 355 AM CDT MON MAR 23 2015
THE MAIN CONCERN IN THE LONG TERM PERIOD WILL BE THE RAIN / SNOW
CHANCES TUESDAY INTO WEDNESDAY AS LOW PRESSURE MOVES ACROSS THE
NORTHERN AND CENTRAL PLAINS. THE 00Z MODELS STILL SHOW SOME
DIFFERENCES IN REGARDS TO THE PROGRESSION OF THE SURFACE
FEATURES...THOUGH THEY GENERALLY SUGGEST TWO LOWS DEVELOPING. THE
NORTHERN LOW IS EXPECTED TO TRACK ACROSS NORTH DAKOTA...WITH THE
ECMWF A LITTLE FARTHER SOUTH THAN THE GFS. THIS CREATES SOME
UNCERTAINTY REGARDING HOW QUICKLY THE COLD AIR RETURNS AND
CONSEQUENTLY SNOW CHANCES. OVERALL...IT APPEARS MUCH OF TUESDAY
WILL SEE TEMPERATURES THROUGHOUT THE ATMOSPHERIC COLUMN SUPPORTING
RAIN...THOUGH THE FAR NORTHWEST COULD SEE A BIT MORE SNOW THAN OTHER
AREAS INITIALLY. ONCE THE COLDER AIR ARRIVES...THE HEAVIER QPF
AMOUNTS ARE FORECAST TO BE EAST OF THE CWA...SO THE OVERALL TREND OF
LESSER SNOW AMOUNTS BY THE LATEST WPC GUIDANCE LOOKS JUSTIFIED.
WILL HAVE A GENERAL AREA OF 1 TO 3 INCHES NORTH OF HIGHWAY 2....WITH
THE HIGHER AMOUNTS NEAR THE INTERNATIONAL BORDER. WINDS WILL BE
ANOTHER CONCERN AS THE LOW PASSES AND COLD AIR ADVECTION TAKES
HOLD. COULD SEE WINDS POTENTIALLY APPROACHING ADVISORY
LEVELS...ESPECIALLY ON WEDNESDAY.
THE REMAINDER OF THE LONG TERM PERIOD IS RELATIVELY QUIET WITH A
WARMING TREND INTO SATURDAY. SATURDAY LOOKS TO BE THE WARMEST DAY
OF THE LONG TERM PERIOD WITH HIGHS POTENTIALLY APPROACHING 70
DEGREES IN SOUTHWEST NORTH DAKOTA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1241 PM CDT MON MAR 23 2015
MVFR CEILINGS TO BEGIN THE 18Z TAF PERIOD AT KISN AND KMOT...WITH
IFR CEILINGS AT KJMS. EXPECT LOW STRATUS TO DISSIPATE IN THESE
AREAS 19-21 UTC. ALREADY STRATUS IS BEGINNING TO SHRINK AND KBIS
HAS CLEARED...THUS VFR CONDITIONS AT KBIS AND KDIK TO BEGIN THE
PERIOD. EASTERLY FLOW WILL BE THE RULE THROUGH THE PERIOD.
ALTHOUGH KDIK AND KISN WILL SEE A SHIFT TO NORTHWEST FLOW AND
INCREASING AFTER 12 UTC TUESDAY. LOW PRESSURE WILL MOVE INTO
WESTERN NORTH DAKOTA LATE TONIGHT WITH RAIN SPREADING INTO THE
AREA...THEN MIXING WITH OR CHANGING TO SNOW OVER THE WEST. MVFR-
IFR CEILINGS/VISIBILITIES ARE EXPECTED ON TUESDAY WITH THIS
SYSTEM.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...CK
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS PORTLAND
237 PM PDT MON MAR 23 2015
.SYNOPSIS...A VIGOROUS COOL WEATHER DISTURBANCE WILL SWING NORTHEAST
THROUGH SOUTHWEST WASHINGTON AND NORTHWEST OREGON TODAY FOR MORE
SHOWERS AND POSSIBLE THUNDERSTORMS AND LOCAL BREEZY CONDITIONS...AND
SOME SNOW IN THE CASCADES. ANOTHER RATHER STRONG LOW WILL APPROACH
THE COAST LATE TODAY AND MOVE FROM WEST TO EAST THROUGH WESTERN
OREGON FOR MORE RAIN AND MOUNTAIN SNOW TONIGHT WITH VERY WINDY
CONDITIONS SOUTH OF THE TRACK OF THE LOW CENTER. SHOWERS WILL
DECREASE TUESDAY AS WE ARE IN BETWEEN SYSTEMS. A WARM FRONT WILL
MOVE NORTHEAST THROUGH THE FORECAST AREA TUESDAY NIGHT AND WEDNESDAY
FOR SOME AREAS OF LIGHT RAIN AS AN UPPER RIDGE BUILDS OFF THE COAST.
THE UPPER RIDGE WILL BRING DRY AND MILD WEATHER TO THE AREA AGAIN
THURSDAY AND FRIDAY. A WEAK AND SPLITTING SYSTEM MAY AFFECT THE AREA
THIS WEEKEND.
&&
.SHORT TERM...THIS AFTERNOON THROUGH THURSDAY...THE SYNOPTIC PICTURE
THIS AFTERNOON LOOKS SIMILAR TO THIS MORNING WITH ONE LOW OFF
VANCOUVER ISLAND AND ANOTHER WELL WEST OF THE OREGON COAST. SHOWERS
CONTINUE LOCALLY AS A VIGOROUS SHORTWAVE AND BAND OF POSITIVE
VORTICITY MOVE NORTH ACROSS THE AREA. THESE FEATURES STILL HAVE A
SLIGHT CHANCE OF HELPING SHOWERS PRODUCE A LIGHTNING STRIKE OR
TWO...BUT CHANCES APPEAR TO BE DWINDLING AS SHOWERS JUST CANNOT SEEM
TO BUILD HIGH ENOUGH FOR LIGHTNING. THE FREEZING LEVEL ON THE SALEM
12Z SOUNDING WAS ONLY ABOUT 4000 FT WHICH HAS ALLOWED SOME PEA-SIZED
HAIL TO FALL WITH SHOWERS...BUT WITH THE -20C LEVEL AT ABOUT 14500
FT...SHOWERS WOULD HAVE TO HAVE SIGNIFICANT HEIGHT TO ACHIEVE
LIGHTNING. HAVE LEFT ONLY A SLIGHT CHANCE OF THUNDER IN THE FORECAST
THROUGH 00Z BUT ADDITIONAL SMALL HAIL SEEMS MORE LIKELY AT THIS
POINT. MOST RECENT HRRR RUN SHOWS WHAT HAS BEEN A CONSISTENT MODEL
TREND OF SHOWERS TAPERING OFF A BIT THROUGH MID AFTERNOON BEFORE RAIN
ASSOCIATED WITH THE NEXT LOW PRESSURE SYSTEM BEGINS TO MOVE IN FROM
THE SOUTH AND SOUTHWEST.
REGARDING THAT LOW...SATELLITE IMAGERY LOCATES IT AROUND 44N 130W
WHICH ISN`T TOO FAR NORTH OF BUOY 2. LATEST PRESSURE READING AT BUOY
2 WAS AROUND 1012 MB WHICH IS ABOUT 2 MB LOWER THAN THE 18Z NAM AND
12Z GFS/ECMWF SHOW AT THE SAME TIME. NO SURPRISE THAT THE MODELS ARE
RUNNING SLIGHTLY WEAK AND BELIEVE THIS BIAS WILL LIKELY APPLY TO THE
STRENGTH OF THE LOW AS IT APPROACHES THE COAST. IN OTHER
WORDS...EXPECT A SLIGHTLY STRONGER LOW THAN MODELS CURRENTLY
INDICATE. WITH THAT BEING SAID...ALL MODELS ARE SHOWING EITHER A
STEADY PRESSURE OR A WEAKENING LOW AS IT APPROACHES THE COAST WHICH
SHOULD LIMIT THE WIND POTENTIAL SOME. 18Z NAM SHOWS 925 MB WINDS OF
50 TO 55 KT ALONG THE COAST AS THE LOW MAKES LANDFALL WHICH COULD BE
A BIT STRONGER WITH THE EXPECTED STRONGER LOW...SO HAVE UPGRADED THE
COAST TO A HIGH WIND WARNING. HOWEVER WITH 925 MB WINDS ACROSS THE
CENTRAL COAST RANGE PEAKING AT ONLY 40 KT IN THE MODELS AND EVEN 850
MB WINDS ONLY 50 KT...DO NOT THINK THAT AREA WILL SEE HIGH WINDS AND
SO HAVE DROPPED HIGH WIND WATCH THERE. THE WIND ADVISORY IN THE
CENTRAL AND SOUTH VALLEY STILL LOOKS GOOD...ESPECIALLY WITH MODELS
TRENDING SLIGHTLY NORTHWARD WITH THE LOW TRACK. EXPECT WINDS TO PICK
UP ON THE COAST STARTING SHORTLY AFTER 00Z AND THEN HIT THE SOUTH
VALLEY STARTING AROUND 04Z AND THEN SPREAD NORTH. WINDS SHOULD BE
DONE ALONG THE COAST SHORTLY AFTER THE LOW MAKES LANDFALL WHICH
CURRENTLY LOOKS LIKE 06Z-ISH...ABOUT 3 HOURS EARLIER THAN PREVIOUS
MODEL RUNS.
THE OTHER ISSUE OVER THE NEXT 12 TO 24 HOURS IS CASCADE SNOW. MODELS
CONTINUE TO TREND HIGHER WITH SNOW LEVELS SO IT LOOKS LIKE SNOW IN
THE LANE COUNTY CASCADES WILL LIKELY BE LIMITED TO ABOVE 4000
FT...BUT THAT`S STILL LOW ENOUGH TO GET SIGNIFICANT ACCUMULATION AT
PASS LEVEL. ELSEWHERE SNOW LEVELS WILL BE A BIT LOWER...CLOSER TO
3500 FT IN THE NORTH OREGON AND SOUTH WASHINGTON CASCADES. DID NOT
SEE ANY NEED TO FURTHER ADJUST SNOW AMOUNTS BUT HAVE OBVIOUSLY
LIMITED LOWER ELEVATION AMOUNTS WITH RISE IN SNOW LEVELS. PEAK SNOW
LOOKS LIKE IT WILL OCCUR FROM LATE EVENING TODAY THROUGH THE
PRE-SUNRISE HOURS TUESDAY BEFORE TAPERING OFF BY MID MORNING. STRONG
WINDS WILL ALSO AFFECT THE CASCADES AND WILL LIKELY PRODUCE SOME
BLOWING SNOW CONDITIONS TONIGHT.
THE LOW WILL MOVE EAST OF THE CASCADES TUESDAY MORNING WITH
DECREASING SHOWERS AND WIND ACROSS OUR AREA ON TUESDAY. AN UPPER
RIDGE IS FORECAST TO BEGIN BUILDING OFF THE COAST TUESDAY...BUT NOT
BEFORE A WARM FRONT SPREADS SOME MORE AREAS OF RAIN AND MOUNTAIN SNOW
INTO SOUTHWEST WASHINGTON AND PARTS OF NORTHWEST OREGON TUESDAY NIGHT
AND WEDNESDAY. AS IT MOVES THROUGH...SNOW LEVELS WILL BEGIN TO
RISE...ESPECIALLY ON WEDNESDAY. HIGH PRESSURE FINALLY LOOKS LIKE IT
WILL TAKE HOLD ON THURSDAY WITH SUNNY SKIES AND WARM TEMPERATURES. WE
COULD SEE OUR FIRST WIDESPREAD 70 DEGREE TEMPERATURES IN THE VALLEY
THURSDAY. BOWEN/TOLLESON
.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...A LOW PRESSURE SYSTEM
IS FORECAST TO RIDE OVER THE CREST OF THE RIDGE OF HIGH PRESSURE IN
PLACE OVER THE PACIFIC NORTHWEST ON FRIDAY. THE QUESTION IS HOW FAR
SOUTH THIS WILL MAKE IT AS IT MOVES ONSHORE. THE MODELS HAVE BEEN
FLIP-FLOPPING A BIT ON WHETHER IT WILL MAKE IT DOWN TO CLIP
SOUTHWEST WASHINGTON/FAR NORTHWEST OREGON OR NOT. AS OF NOW...THE
GFS IS SHOWING A CHANCE OF RAIN MAKING IT DOWN TO THE FAR NORTHERN
PORTION OF OUR AREA...BUT THE LAST FEW RUNS HAVE BEEN KEEPING IT
FURTHER NORTH.WE HAVE INTRODUCED A SLIGHT CHANCE OF RAIN FOR THIS
NORTHERN PORTION OF OUR AREA FOR FRIDAY NIGHT TO SHOW THIS
UNCERTAINTY. FOR SATURDAY WE GET INTO SOUTH-SOUTHWESTERLY FLOW WITH
HIGH PRESSURE TO OUR NORTH AND A BROAD LOW OVER THE SOUTHWESTERN US.
THIS BRINGS MOISTURE UP FROM THE SOUTH PACIFIC WHICH IS A PATTERN
FAVORABLE FOR SHOWERS IN THE CASCADES. THIS SSW-ERLY FLOW ONLY
INCREASES ON SUNDAY AS A THERMAL LOW DEVELOPS OVER NORTHERN
CALIFORNIA. THIS WILL KEEP A CHANCE OF SHOWERS IN THE CASCADES
THROUGH SUNDAY. MODELS ARE SUGGESTING A WEAK FRONT WILL MOVE THROUGH
EARLY NEXT WEEK WHICH BRINGS US ANOTHER CHANCE OF RAIN ACROSS THE
AREA MONDAY AND TUESDAY. -MCCOY
&&
.AVIATION...A SHOWERY UNSTABLE AIR MASS WILL LEAD TO PRIMARILY
VFR CONDITIONS WITH ONLY AN OCCASIONAL AND BRIEF MVFR FLIGHT
RESTRICTION AT ALL TAF SITES LATE THIS AFTERNOON AND EARLY THIS
EVENING. THERE IS A SLIGHT CHANCE OF THUNDERSTORM THROUGH 02Z
TUESDAY...BUT CONFIDENCE IN TIMING AND COVERAGE IS HIGH ENOUGH TO
PREVENT PUTTING THE MENTION IN ANY TAF.
A LOW PRESSURE MOVING EASTWARD INTO THE NORTH OREGON COAST
TONIGHT AND WILL SPREAD STEADY RAIN INTO THE AREA THIS EVENING.
THIS SHOULD RESULT IN MANY LOCATIONS DETERIORATING INTO MVFR
CONDITIONS...PRIMARILY CENTERED BETWEEN 03Z AND 15Z TUESDAY. AS
THE LOW PRESSURE PUSHES ASHORE AND INLAND...SOUTH WIND GUSTS OF 50
KT AT KONP AND 40 KT AT KSLE AND KEUG APPEAR POSSIBLE FOR A 2 TO 4
HOUR PERIOD BETWEEN 03Z AND 09Z TUESDAY. CONDITIONS SHOULD TREND
VFR AT THESE TAF SITES WHEN THESE STRONGER SOUTH WINDS
SURFACE...PARTICULARLY AT KSLE AND KEUG.
KPDX AND APPROACHES...A SHOWERY UNSTABLE AIR MASS WILL LEAD TO
PRIMARILY VFR CONDITIONS WITH ONLY BRIEF TEMPORARY MVFR CONDITIONS
UNDER HEAVIER SHOWERS. THERE MAY BE A MORE EXTENDED PERIOD OF MVFR
CONDITIONS TONIGHT AS THE LOWER ATMOSPHERE STABILIZES AND WINDS
RELAX...PRIMARILY BETWEEN 06Z AND 15Z TUESDAY. /NEUMAN
&&
.MARINE...MODELS ARE CONTINUING TO COME INTO BETTER AGREEMENT THAT A
LOW PRESSURE WILL MOVE EASTWARD INTO THE NORTH CENTRAL OREGON
COAST TONIGHT. THE LATEST ROUND OF SHORT TERM FORECAST MODELS
SUGGEST THE LOW PRESSURE WILL MAKE LANDFALL SOMEWHERE BETWEEN
NEWPORT AND TILLAMOOK. LANDFALL IS EXPECTED TO OCCUR AROUND
MIDNIGHT...AT WHICH POINT...WINDS WILL BEGIN TO EASE ACROSS THE
WATERS. THE STRONGEST WINDS ARE EXPECTED TO REMAIN SOUTH OF THE
LOW PRESSURE TRACK. AS A RESULT...SOLID GALE FORCE WINDS OF 35 TO
45 KT APPEAR LIKELY ACROSS THE CENTRAL OREGON WATERS FOR A 3 TO 5
HOUR PERIOD LATE THIS EVENING. THIS SHOULD ALLOW SEAS TO CLIMB
INTO THE 12 TO 15 FT RANGE ACROSS THE CENTRAL OREGON WATERS.
FARTHER NORTH...SEAS SHOULD TEMPORARILY JUMP ABOVE 10 FT
OVERNIGHT...BUT DURATION REMAINS SOMEWHAT IN QUESTION.
INCREASING HIGH PRESSURE WILL BRING A BREAK IN THE WINDS AND ALLOW
SEAS TO RELAX TUESDAY. HOWEVER...A WEAK FRONT WILL PUSH INTO THE
WATERS TUESDAY NIGHT AND WEDNESDAY MORNING. THIS SHOULD PRODUCE
SMALL CRAFT ADVISORY LEVEL SOUTH WINDS OF 25 KT ACROSS THE
WATERS...PARTICULARLY OVER THE NORTHERN OUTER WATERS DURING THIS
PERIOD.
HIGH PRESSURE OVER THE NORTHEAST PACIFIC AND THERMAL LOW PRESSURE
OVER NORTHERN CALIFORNIA WILL THEN ARRIVE LATE THIS WEEK AND OVER
THE WEEKEND...AND PRODUCE A MORE SUMMER-LIKE NORTHERLY WIND
PATTERN. A WEAK FRONT COULD TEMPORARILY ENHANCE WIND GUSTS ACROSS
THE WATERS ON FRIDAY. /NEUMAN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 9 PM THIS EVENING TO 5 AM PDT TUESDAY FOR
CENTRAL WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
WINTER WEATHER ADVISORY UNTIL 7 AM PDT TUESDAY FOR CASCADES IN
LANE COUNTY-NORTHERN OREGON CASCADES.
HIGH WIND WARNING FROM 5 PM THIS AFTERNOON TO 3 AM PDT TUESDAY
FOR CENTRAL OREGON COAST.
WA...WINTER WEATHER ADVISORY UNTIL 7 AM PDT TUESDAY FOR SOUTH
WASHINGTON CASCADES.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 3 AM PDT TUESDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 3 AM PDT TUESDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT THIS AFTERNOON FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM PDT TUESDAY FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 PM THIS
AFTERNOON TO 11 PM PDT THIS EVENING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
10 AM PDT TUESDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
629 PM EDT MON MAR 23 2015
.SYNOPSIS...
A WEAK AND FAST MOVING ALBERTA CLIPPER WILL BRING LIGHT SNOW TO
SOUTHERN PARTS OF THE FORECAST AREA TONIGHT. LOW PRESSURE MOVING
TO OUR NORTH WILL BRING MILDER TEMPERATURES WITH A FEW PERIODS OF
RAIN FOR WEDNESDAY INTO THURSDAY. MUCH COOLER AND DRIER CONDITIONS
WILL RETURN FOR FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
CLOUDS RAPIDLY OVERSPREADING CENTRAL PA THIS EVENING IN ADVANCE
OF APPROACHING CLIPPER. UPSTREAM RADAR/SFC OBS...COMBINED WITH
NEAR TERM MDL DATA...SUPPORT INCREASING POPS TO NEAR 100 PCT
ACROSS THE LAUREL HIGHLANDS TONIGHT. BASED ON INPUT OF LATEST
HRRR/4KM NAM...HAVE EXPANDED THE AREAL COVERAGE OF MEASURABLE SNOW
A BIT...BUT OVERALL QPF HASN/T INCREASED APPRECIABLY. STILL
FAVORING ACCUMS FROM 1-3 INCHES ACROSS THE LAUREL HIGHLANDS OF
SOMERSET/CAMBRIA COUNTIES...TO A COATING ACROSS THE CENTRAL MTNS
AND PORTIONS OF THE LOWER SUSQ VALLEY.
RADAR AND HRRR OUTPUT SUGGEST SNOW SHOULD REACH THE LAUREL
HIGHLANDS BTWN 00Z-02Z BEFORE SPREADING EAST ACROSS THE REMAINDER
OF SOUTHERN PA OVERNIGHT. MID LVL SHORTWAVE AND BULK OF LG SCALE
FORCING SHOULD BE PUSHING EAST OF THE AREA SHORTLY AFTER
06Z...CAUSING SNOW TO TAPER OFF ARND THAT TIME.
LOWS WILL ONCE AGAIN BE WELL BELOW NORMAL TONIGHT...RANGING FROM
THE MID TEENS OVER THE FAR NORTH TO MID 20S OVER THE SOUTH.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SPOTTY LIGHT SNOW COULD LINGER DURING THE MORNING OVER SOUTHERN
SECTIONS IN THE INVERTED SURFACE TROUGH AND LOW LEVEL UPSLOPE
FLOW SOUTH OF THE HIGH THAT WILL BE NORTH OF NEW YORK. LATEST
TIMING SUGGESTS TUESDAY AFTERNOON WILL SEE CLOUDS BREAKING UP
AND SNOW COMING TO AN END.
TEMPERATURES WILL REBOUND INTO THE UPPER 30S TO MID 40S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
FAIRLY ZONAL FLOW...BUT SOMEWHAT BUMPY IN THE NORTHERN
STREAM...WILL HOLD THROUGH THE EARLY PART OF THE LONG TERM PERIOD.
SOME OF THIS ENERGY IS FORECAST TO LEAD TO AMPLIFICATION OF AN
UPPER TROF OVER THE NORTHERN PLAINS MID WEEK...AND AN EVEN DEEPER
UPPER TROF OVER EASTERN U.S. BY LATE IN THE WEEK. THIS AMPLIFYING
PATTERN HOWEVER IS FORECAST TO REMAIN PROGRESSIVE.
THE DEVELOPING TROF WILL BRING A WARM FRONT/COLD FRONT COMBO
ACROSS PA WED INTO THURSDAY. AHEAD OF THE COLD FRONT...TEMPS
SHOULD CLIMB INTO THE 50S AND 60S...LEVELS NOT SEEN SINCE LAST
FALL. ANOTHER TUMBLE IN TEMPS IS EXPECTED BEHIND THE SYSTEM FOR
LATE IN THE WEEK.
EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND
THIS SYSTEM WITH SEVERAL DRY DAYS INTO NEXT WEEKEND. ANOTHER COLD
FRONT WILL MOVE THROUGH LATE SUNDAY INTO NEXT MONDAY BRINGING
ANOTHER RETURN TO CHILLY TEMPS AS WELL AS THE CHANCE FOR MORE
SNOW SHOWERS.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MADE A FEW MORE CHANGES TO THE 00Z TAFS.
JUST HIGH CLDS OUTSIDE THE OFFICE...BUT THICKER CLDS JUST
TO THE WEST. VERY FAST MOVING SYSTEM MOVING SE TOWARD CENTRAL
PA.
A WEAK SYSTEM TRACKING ESEWD FROM THE MIDWEST/OH VALLEY WILL
BRING A PERIOD OF LIGHT SNOW AND REDUCED VIS/CIGS TO THE SWRN HALF
OF THE LOCAL FLYING AREA FROM THIS EVENING INTO EARLY TUESDAY
MORNING.
THE LOWER CIGS/VIS WILL LINGER INTO TUESDAY MORNING FROM JST-AOO
SOUTHWARD...BEFORE GRADUALLY IMPROVING LATER TUES MORNING.
EXPECT VFR BY TUESDAY AFTERNOON AS HIGH PRES MIGRATES ACROSS THE
AIRSPACE.
OUTLOOK...
WED-FRI...PERIODS OF RAIN AND MVFR/IFR CONDITIONS.
SAT...MAINLY VFR...PERHAPS A BRIEF PERIOD OF MVFR
ACROSS THE WEST AND NW.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
545 PM EDT MON MAR 23 2015
.SYNOPSIS...
A WEAK AND FAST MOVING ALBERTA CLIPPER WILL BRING LIGHT SNOW TO
SOUTHERN PARTS OF THE FORECAST AREA TONIGHT. LOW PRESSURE MOVING
TO OUR NORTH WILL BRING MILDER TEMPERATURES WITH A FEW PERIODS OF
RAIN FOR WEDNESDAY INTO THURSDAY. MUCH COOLER AND DRIER CONDITIONS
WILL RETURN FOR FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
CLOUDS RAPIDLY OVERSPREADING CENTRAL PA THIS EVENING IN ADVANCE
OF APPROACHING CLIPPER. UPSTREAM RADAR/SFC OBS...COMBINED WITH
NEAR TERM MDL DATA...SUPPORT INCREASING POPS TO NEAR 100 PCT
ACROSS THE LAUREL HIGHLANDS TONIGHT. BASED ON INPUT OF LATEST
HRRR/4KM NAM...HAVE EXPANDED THE AREAL COVERAGE OF MEASURABLE SNOW
A BIT...BUT OVERALL QPF HASN/T INCREASED APPRECIABLY. STILL
FAVORING ACCUMS FROM 1-3 INCHES ACROSS THE LAUREL HIGHLANDS OF
SOMERSET/CAMBRIA COUNTIES...TO A COATING ACROSS THE CENTRAL MTNS
AND PORTIONS OF THE LOWER SUSQ VALLEY.
RADAR AND HRRR OUTPUT SUGGEST SNOW SHOULD REACH THE LAUREL
HIGHLANDS BTWN 00Z-02Z BEFORE SPREADING EAST ACROSS THE REMAINDER
OF SOUTHERN PA OVERNIGHT. MID LVL SHORTWAVE AND BULK OF LG SCALE
FORCING SHOULD BE PUSHING EAST OF THE AREA SHORTLY AFTER
06Z...CAUSING SNOW TO TAPER OFF ARND THAT TIME.
LOWS WILL ONCE AGAIN BE WELL BELOW NORMAL TONIGHT...RANGING FROM
THE MID TEENS OVER THE FAR NORTH TO MID 20S OVER THE SOUTH.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SPOTTY LIGHT SNOW COULD LINGER DURING THE MORNING OVER SOUTHERN
SECTIONS IN THE INVERTED SURFACE TROUGH AND LOW LEVEL UPSLOPE
FLOW SOUTH OF THE HIGH THAT WILL BE NORTH OF NEW YORK. LATEST
TIMING SUGGESTS TUESDAY AFTERNOON WILL SEE CLOUDS BREAKING UP
AND SNOW COMING TO AN END.
TEMPERATURES WILL REBOUND INTO THE UPPER 30S TO MID 40S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
FAIRLY ZONAL FLOW...BUT SOMEWHAT BUMPY IN THE NORTHERN
STREAM...WILL HOLD THROUGH THE EARLY PART OF THE LONG TERM PERIOD.
SOME OF THIS ENERGY IS FORECAST TO LEAD TO AMPLIFICATION OF AN
UPPER TROF OVER THE NORTHERN PLAINS MID WEEK...AND AN EVEN DEEPER
UPPER TROF OVER EASTERN U.S. BY LATE IN THE WEEK. THIS AMPLIFYING
PATTERN HOWEVER IS FORECAST TO REMAIN PROGRESSIVE.
THE DEVELOPING TROF WILL BRING A WARM FRONT/COLD FRONT COMBO
ACROSS PA WED INTO THURSDAY. AHEAD OF THE COLD FRONT...TEMPS
SHOULD CLIMB INTO THE 50S AND 60S...LEVELS NOT SEEN SINCE LAST
FALL. ANOTHER TUMBLE IN TEMPS IS EXPECTED BEHIND THE SYSTEM FOR
LATE IN THE WEEK.
EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND
THIS SYSTEM WITH SEVERAL DRY DAYS INTO NEXT WEEKEND. ANOTHER COLD
FRONT WILL MOVE THROUGH LATE SUNDAY INTO NEXT MONDAY BRINGING
ANOTHER RETURN TO CHILLY TEMPS AS WELL AS THE CHANCE FOR MORE
SNOW SHOWERS.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
MINOR ADJUSTMENTS MADE TO 21Z TAFS.
JUST HIGH CLDS OUTSIDE THE OFFICE...BUT THICKER CLDS JUST
TO THE WEST. VERY FAST MOVING SYSTEM MOVING SE TOWARD CENTRAL
PA.
EARLIER DISCUSSION BELOW.
WIDESPREAD VFR WILL PREVAIL THROUGH THE AFTERNOON WITH MID-HIGH
CLOUDS INCREASING FROM NW TO SE AFTER 18-21Z.
A WEAK SYSTEM TRACKING ESEWD FROM THE MIDWEST/OH VALLEY WILL
BRING A PERIOD OF LIGHT SNOW AND REDUCED VIS/CIGS TO THE SWRN HALF
OF THE LOCAL FLYING AREA FROM THIS EVENING INTO EARLY TUESDAY
MORNING.
THE LOWER CIGS/VIS WILL LINGER INTO TUESDAY MORNING FROM JST-AOO
SOUTHWARD...BEFORE GRADUALLY IMPROVING LATER TUES MORNING.
EXPECT VFR BY TUESDAY AFTERNOON AS HIGH PRES MIGRATES ACROSS THE
AIRSPACE.
OUTLOOK...
WED-FRI...PERIODS OF RAIN AND MVFR/IFR CONDITIONS.
SAT...MAINLY VFR...PERHAPS A BRIEF PERIOD OF MVFR
ACROSS THE WEST AND NW.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
346 PM CDT MON MAR 23 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 346 PM CDT MON MAR 23 2015
STRATUS DECK CONTINUES TO ERODE QUICKLY FROM SOUTHWEST TO
NORTHEAST ACROSS THE EASTERN CWA WITH TEMPS QUICKLY CLIMBING AS
THE SUN EMERGES. SNOWFALL FROM YESTERDAY WILL BE HISTORY FOR SOME
AREAS. ONCE AGAIN THE HRRR LOW-LEVEL CLOUD COVER PRODUCT PERFORMED
EXTREMELY WELL IN ERODING THE STRATUS DECK THIS AFTERNOON.
ATTENTION THEN TURNS TO THE STORM SYSTEM MOVING IN TONIGHT.
SHOWERS ARE ALREADY NOTED ACROSS SOUTHWEST SD AND APPROACHING THE
SOUTHWEST CWA. MODELS ARE COMING INTO BETTER AGREEMENT WITH A
DRIER SOLUTION OVER THE CWA. THAT SAID THOUGH...IT STILL APPEARS A
BAND OF WARM AIR ADVECTION RAINFALL WILL MOVE EASTWARD ACROSS THE
AREA LATE TONIGHT AND THROUGH THE DAY TUESDAY. ITS A QUESTION OF
JUST HOW FILLED IN AND INTENSE THIS BAND WILL BE. BACKED OFF ON
QPF A BIT THOUGH AS MODELS ARE RATHER LIGHT WITH ITS QPF OUTPUT.
OVERALL FORCING IS MODEST. COULD STILL BE DEALING WITH MIXED
PRECIP ACROSS THE EASTERN CWA LATE TONIGHT AND THROUGH THE DAY
TUESDAY. MODELS ALL SHOWING A DRY SLOT MOVING INTO THE WESTERN CWA
TUESDAY AFTERNOON...WITH BREEZY WEST TO NORTHWEST WINDS AND DRYING
CONDITIONS. RH VALUES WILL LIKELY FALL INTO THE 20S ACROSS THE
SOUTHWEST CWA ONCE AGAIN. TEMPS WILL WARM NICELY IN THE DRY
SLOT...ESPECIALLY OVER THE SOUTHWEST CWA AND MAY HAVE TO BUMP UP
HIGHS A FEW MORE DEGREES.
AS THE LOW PASSES TO THE EAST ON WEDNESDAY...STRONG NORTHWEST
WINDS DEVELOP. COULD BE CLOSE TO WIND ADVISORY LEVELS SO WILL HAVE
TO KEEP AN EYE ON THAT. WILL ALSO HAVE TO WATCH WRAP AROUND PRECIP
POTENTIAL ON THE BACK SIDE OF THE LOW. THERE ARE DISCREPANCIES IN
JUST HOW FAR SOUTH PRECIP WILL MAKE IT...WITH THE GFS THE FURTHEST
SOUTH THROUGH MUCH OF NORTHEAST SD AND WEST CENTRAL MN. THE EC
DOES NOT TAKE IT MUCH SOUTH OF THE ND/SD BORDER. GENERALLY WENT
WITH THE MORE RELIABLE EC AT THIS POINT. INTERESTING TO NOTE
THOUGH THAT THIS TIME AROUND THE GEM IS IN AGREEMENT WITH THE GFS.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 346 PM CDT MON MAR 23 2015
UPPER LEVEL PATTERN WILL TRANSITION FROM NORTHWEST FLOW TO A FLAT
RIDGE WITH SEVERAL WAVES PASSING THROUGH. THIS WILL RESULT IN
FLUCTUATING TEMPS THROUGH THE PERIOD. PATTERN DOES LOOK MOSTLY
DRY AS BEST UPPER ENERGY REMAINS NORTH OF THE STATE. TEMPS WILL
BE COOLEST ON THURSDAY...WITH A WARMING TREND INTO
SATURDAY...WHERE TEMPS WILL BE ABOVE NORMAL MOST LOCATIONS...SPLY
ALONG AND WEST OF THE MISSOURI RIVER. A STRONGER WAVE CRASHES
THROUGH THE RIDGE ON SATURDAY NIGHT BRINGING BREEZY CONDITIONS
AND COOLER TEMPS FOR SUNDAY...THEN A REBOUND OF TEMPS AGAIN FOR
MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1229 PM CDT MON MAR 23 2015
IFR AND LIFR CIGS DUE TO FOG AT KABR AND KATY WILL SLOWLY
DISSIPATE THIS AFTERNOON. THE NEXT SYSTEM WILL ARRIVE TUESDAY
MORNING AND SPREAD IFR/MVFR CIGS FROM THE WEST TO EAST WITH AREAS
OF FOG AND LIGHT RAIN DEVELOPING.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...TMT
LONG TERM...SCARLETT
AVIATION...SCARLETT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
515 PM CDT MON MAR 23 2015
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 228 PM CDT MON MAR 23 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ONE
SHORTWAVE EXITING THE REGION OVER SOUTHERN LAKE MICHIGAN...WHILE
ANOTHER SHORTWAVE IS MOVING SOUTHEAST OVER NORTHERN MINNESOTA. MID
AND HIGH CLOUDS ARE PULLING OUT OVER NORTHERN LAKE MICHIGAN
ASSOCIATED WITH THE FIRST SHORTWAVE...BUT ANOTHER ROUND OF CLOUDS
IS INCOMING FROM THE LATTER SHORTWAVE...ALONG WITH LIGHT SNOW OVER
NORTHERN MINNESOTA. PLENTY OF DRY AIR PRESENT ACCORDING TO THE 12Z
SOUNDING BELOW 700MB WHICH THE UPSTREAM LIGHT SNOWFALL WILL HAVE TO
OVERCOME IF IT SURVIVES THE TRIP INTO N-C WISCONSIN LATER TODAY.
PLENTY OF LOW CLOUDS ARE LINGERING OVER CENTRAL WISCONSIN ALONG A
LOW LEVEL THERMAL GRADIENT...BUT THE DRY AIR IS HALTING ANY ADVANCE
TO THE NORTHEAST. CONCERNS THROUGH TOMORROW AFTERNOON ARE RELATIVELY
MINOR...AND CENTER AROUND CLOUDS AND TEMPS.
TONIGHT...A COMPACT SHORTWAVE WILL MOVE ACROSS NORTHEAST WISCONSIN
THIS EVENING. EVEN THOUGH THERE IS LIGHT SNOW AHEAD OF IT
CURRENTLY...IT WILL RUN INTO MUCH DRIER AIR BELOW 10KFT AS IT MOVES
INTO NORTHERN WISCONSIN. PROGGED SOUNDINGS SHOW THIS DRY AIR WEDGE
WELL TONIGHT...SO THINK WE WILL ONLY SEE SCATTERED TO BROKEN
MID-CLOUDS THROUGH THE EVENING...THEN CLEARING SKIES OVERNIGHT.
TEMPS FALLING INTO THE TEENS IN THE NORTH AND LOW TO MID 20S SOUTH.
TUESDAY...DRY CANADIAN HIGH PRESSURE HANGS ON FOR ONE MORE DAY.
WILL SEE INCREASING CIRRUS DURING THE AFTERNOON AHEAD OF A STORM
SYSTEM MOVING OVER THE CENTRAL PLAINS...BUT SHOULD SEE A GOOD DEAL
OF SUNSHINE. 925MB TEMPS CONTINUE TO BE CHILLY WITHIN THIS AIRMASS
SO DROPPED MAX TEMPS A DEGREE. HIGHS MAINLY IN THE LOW TO MID 40
EXCEPT COOLER NEAR THE LAKE.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 228 PM CDT MON MAR 23 2015
SYSTEM FOR TUESDAY NIGHT INTO WEDNESDAY MORNING STILL PROBLEMATIC
WITH RESPECT TO EXACT TRACK OF THE SYSTEM...AMOUNT OF WARM AIR AT
THE SURFACE AND ALOFT...AND AMOUNT OF EVAPORATIVE COOLING THAT
WILL TAKE PLACE THAT MAY WIPE OUT THE WARM LAYER.
CONTEMPLATED A WINTER STORM WATCH DUE TO THE IMPACTS THIS SYSTEM
WOULD HAVE ON THE ROADS AND FOR THE MORNING RUSH HOUR. PER
COORDINATION WITH SURROUNDING OFFICES...DECIDED TO GO WITH A
SPECIAL WEATHER STATEMENT TO HIGHLIGHT THE IMPACTS OF THIS SYSTEM.
WITH SYSTEM TRENDING FURTHER SOUTH...THIS WILL HAVE IMPACTS ON
PRECIPITATION TYPES AND SNOW AMOUNTS ACROSS THE FORECAST AREA.
ADDED MORE SNOW TO THE FORECAST DUE TO THE COLDER TEMPERATURES
AT THE SURFACE AND ALOFT THAN PREVIOUS SHIFT. TO SHOW YOU THE
COMPLEXITY OF THE FORECAST...GRB NAM BUFKIT SOUNDING INDICATED
0.4 INCHES OF ICE WHILE THE GFS SUPPORTED 3 TO 5 INCHES OF SNOW.
TRENDED TOWARD THE GFS SOLUTION SINCE CANADIAN/ECMWF MODEL
SUPPORTED THE COLDER GFS SOLUTION. ALSO...THE SPEED OF THE SYSTEM
WAS OF CONCERN. HEAVIEST PRECIPITATION WOULD FALL IN ABOUT A 6 HOUR
PERIOD. THOSE TYPE OF EVENTS USUALLY DO NOT GET US TO WARNING CRITERIA.
SYSTEM WILL EXIT THE REGION WEDNESDAY MORNING WITH COLD CYCLONIC
FLOW NOTED INTO THE FIRST PART OF THE WEEKEND. CHANCE OF RAIN OR
SNOW WILL LINGER INTO THURSDAY BEFORE DRIER AIR ARRIVES. THE NEXT
CHANCE FOR RAIN OR SNOW WOULD BE SATURDAY NIGHT AND SUNDAY.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 515 PM CDT MON MAR 23 2015
SURFACE HIGH PRESSURE SYSTEM ANCHORED OVER THE GREAT LAKES REGION
WILL PROVIDE VFR CONDITIONS TONIGHT INTO TUESDAY. DETERIORATING
CONDITIONS ANTICIPATED TUESDAY NIGHT AS A STRONG FRONTAL SYSTEM
LIFTS TOWARD WISCONSIN. THE LOWERING CIGS AND VSBYS WILL INCLUDE A
WINTRY MIX OF SNOW SLEET AND FREEZING RAIN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 228 PM CDT MON MAR 23 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ONE
SHORTWAVE EXITING THE REGION OVER SOUTHERN LAKE MICHIGAN...WHILE
ANOTHER SHORTWAVE IS MOVING SOUTHEAST OVER NORTHERN MINNESOTA. MID
AND HIGH CLOUDS ARE PULLING OUT OVER NORTHERN LAKE MICHIGAN
ASSOCIATED WITH THE FIRST SHORTWAVE...BUT ANOTHER ROUND OF CLOUDS
IS INCOMING FROM THE LATTER SHORTWAVE...ALONG WITH LIGHT SNOW OVER
NORTHERN MINNESOTA. PLENTY OF DRY AIR PRESENT ACCORDING TO THE 12Z
SOUNDING BELOW 700MB WHICH THE UPSTREAM LIGHT SNOWFALL WILL HAVE TO
OVERCOME IF IT SURVIVES THE TRIP INTO N-C WISCONSIN LATER TODAY.
PLENTY OF LOW CLOUDS ARE LINGERING OVER CENTRAL WISCONSIN ALONG A
LOW LEVEL THERMAL GRADIENT...BUT THE DRY AIR IS HALTING ANY ADVANCE
TO THE NORTHEAST. CONCERNS THROUGH TOMORROW AFTERNOON ARE RELATIVELY
MINOR...AND CENTER AROUND CLOUDS AND TEMPS.
TONIGHT...A COMPACT SHORTWAVE WILL MOVE ACROSS NORTHEAST WISCONSIN
THIS EVENING. EVEN THOUGH THERE IS LIGHT SNOW AHEAD OF IT
CURRENTLY...IT WILL RUN INTO MUCH DRIER AIR BELOW 10KFT AS IT MOVES
INTO NORTHERN WISCONSIN. PROGGED SOUNDINGS SHOW THIS DRY AIR WEDGE
WELL TONIGHT...SO THINK WE WILL ONLY SEE SCATTERED TO BROKEN
MID-CLOUDS THROUGH THE EVENING...THEN CLEARING SKIES OVERNIGHT.
TEMPS FALLING INTO THE TEENS IN THE NORTH AND LOW TO MID 20S SOUTH.
TUESDAY...DRY CANADIAN HIGH PRESSURE HANGS ON FOR ONE MORE DAY.
WILL SEE INCREASING CIRRUS DURING THE AFTERNOON AHEAD OF A STORM
SYSTEM MOVING OVER THE CENTRAL PLAINS...BUT SHOULD SEE A GOOD DEAL
OF SUNSHINE. 925MB TEMPS CONTINUE TO BE CHILLY WITHIN THIS AIRMASS
SO DROPPED MAX TEMPS A DEGREE. HIGHS MAINLY IN THE LOW TO MID 40
EXCEPT COOLER NEAR THE LAKE.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 228 PM CDT MON MAR 23 2015
SYSTEM FOR TUESDAY NIGHT INTO WEDNESDAY MORNING STILL PROBLEMATIC
WITH RESPECT TO EXACT TRACK OF THE SYSTEM...AMOUNT OF WARM AIR AT
THE SURFACE AND ALOFT...AND AMOUNT OF EVAPORATIVE COOLING THAT
WILL TAKE PLACE THAT MAY WIPE OUT THE WARM LAYER.
CONTEMPLATED A WINTER STORM WATCH DUE TO THE IMPACTS THIS SYSTEM
WOULD HAVE ON THE ROADS AND FOR THE MORNING RUSH HOUR. PER
COORDINATION WITH SURROUNDING OFFICES...DECIDED TO GO WITH A
SPECIAL WEATHER STATEMENT TO HIGHLIGHT THE IMPACTS OF THIS SYSTEM.
WITH SYSTEM TRENDING FURTHER SOUTH...THIS WILL HAVE IMPACTS ON
PRECIPITATION TYPES AND SNOW AMOUNTS ACROSS THE FORECAST AREA.
ADDED MORE SNOW TO THE FORECAST DUE TO THE COLDER TEMPERATURES
AT THE SURFACE AND ALOFT THAN PREVIOUS SHIFT. TO SHOW YOU THE
COMPLEXITY OF THE FORECAST...GRB NAM BUFKIT SOUNDING INDICATED
0.4 INCHES OF ICE WHILE THE GFS SUPPORTED 3 TO 5 INCHES OF SNOW.
TRENDED TOWARD THE GFS SOLUTION SINCE CANADIAN/ECMWF MODEL
SUPPORTED THE COLDER GFS SOLUTION. ALSO...THE SPEED OF THE SYSTEM
WAS OF CONCERN. HEAVIEST PRECIPITATION WOULD FALL IN ABOUT A 6 HOUR
PERIOD. THOSE TYPE OF EVENTS USUALLY DO NOT GET US TO WARNING CRITERIA.
SYSTEM WILL EXIT THE REGION WEDNESDAY MORNING WITH COLD CYCLONIC
FLOW NOTED INTO THE FIRST PART OF THE WEEKEND. CHANCE OF RAIN OR
SNOW WILL LINGER INTO THURSDAY BEFORE DRIER AIR ARRIVES. THE NEXT
CHANCE FOR RAIN OR SNOW WOULD BE SATURDAY NIGHT AND SUNDAY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1208 PM CDT MON MAR 23 2015
VFR CONDITIONS THROUGH THE TAF FORECAST WITH PERIODS OF MID AND HIGH
CLOUDS THROUGH THE EVENING...THEN CLEARING OUT OVERNIGHT. AS A HEADS
UP...HEAVY PRECIP IS POSSIBLE TUESDAY NIGHT WITH SEVERAL INCHES OF
SNOW POSSIBLE. THE MOST LIKELY SCENARIO IS FOR THIS SNOW TO FALL
NORTH AND WEST OF THE FOX VALLEY...A WINTRY MIX OF
SNOW/SLEET/FREEZING RAIN OVER THE FOX VALLEY AND POINTS EAST.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC