Low Pressure near Northern Leewards

[wxman57]

Convection has increased a bit, but the low center appears more elongated this afternoon. Could be an invest at any time, though it's fighting plenty of shear.

[cycloneye]

[Derek Ortt]

surface inflow has also improved significantly this afternoon, indicative of increased low-level convergence

[AJC3]

Convection has increased a bit, but the low center appears more elongated this afternoon. Could be an invest at any time, though it's fighting plenty of shear.

Yeah, and I don't really see where this thing could find conditions that are anything less than hostile. In another h36-h48 the area where it is at now should start to become affecting by strong UL winds on the back side of the massive ULL centered near 31N 42W and dropping SW-ward. Between h36 and h72, both the ECM and GFS are developing a small H25 trough somewhere between 20-30N near 70W.

Finally, if the system was to drop SW into the Caribbean, it would still encounter strong W and NW shear on the east side of the developing UL anticyclone over the western Caribbean.

[cycloneye]

AFD from the NWS in San Juan,Puerto Rico:

FXCA62 TJSJ 242051
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
451 PM AST WED OCT 24 2007

.SYNOPSIS...
BROAD HIGH PRESSURE RIDGE IS SPREAD ACROSS THE NORTHWESTERN
CARIBBEAN AND EXTENDS NORTH AND SOUTHEAST ACROSS THE GREATER
ANTILLES AND SOUTHEAST CARIBBEAN RESPECTIVELY. LOW PRESSURE
TROUGH/TUTT AND ASSOCIATED LOW EXTENDS SOUTHWEST FROM THE EAST
ATLANTIC TO JUST NORTH OF THE LOCAL REGION. AT LOW LEVELS THIS
FEATURE IS INDUCING A LOW LEVEL CIRCULATION NOW OBSERVED DOWN TO
THE SURFACE. THIS FEATURE WAS OBSERVED JUST NORTHEAST OF THE
NORTHERN LEEWARDS. SIGNIFICANT CLOUDINESS AND CONVECTIVE ACTIVITY
WAS NOTED TO THE NORTH AND EAST OF THE LOW LEVEL CIRCULATION WHICH
WAS INFLUENCED BY THE WESTERLY SHEAR IN THE UPPER LEVELS.

A WEAK TROPICAL WAVE NEAR 64 WEST THIS AFTERNOON WILL CONTINUE TO
MOVE ACROSS THE SOUTHERN CARIBBEAN WATERS AND HAVE LITTLE EFFECT
ON THE LOCAL AREA.

&&

.DISCUSSION...
DIURNAL AND LOCAL TERRAIN EFFECTS COMBINED WITH AVAILABLE MOISTURE
AND MARGINAL UPPER LEVEL INSTABILITY...MADE FOR THE DEVELOPMENT
OF AFTERNOON SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE WEST
INTERIOR AND SOUTHWEST SECTIONS OF PUERTO RICO. SOME OF THE SHOWERS
AND STORMS PRODUCED LOCALLY HEAVY RAINFALL WHICH LEAD TO URBAN
FLOODING IN SOME AREAS. THE U.S. VIRGIN ISLANDS ALSO RECEIVED
BRIEF PERIODS OF LOCALLY HEAVY RAINFALL DURING THE AFTERNOON
HOURS.

THE SURFACE LOW AND ASSOCIATED TROUGH EAST OF THE NORTHERN
LEEWARD ISLANDS IS FORECAST OF MOVE WEST SOUTHWEST AND INTO THE
CENTRAL CARIBBEAN OVER THE NEXT FEW DAYS. AS A RESULT EXPECT AN
ABUNDANCE OF TROPICAL MOISTURE TO MAKE ITS WAY ACROSS THE LOCAL
REGION THROUGH THE END OF THE WEEK. THE PROXIMITY OF THE MID TO
UPPER LEVE TROUGH WILL PROVIDE SUFFICIENT INSTABILITY TO COMBINE
WITH AND ENHANCE DIURNAL AND NOCTURNAL CONVECTION ACROSS THE LOCAL
ISLANDS AND REGIONAL WATERS. THEREFORE EXPECT PERIODS OF HEAVY
SHOWERS WITH ISOLATED BUT STRONG THUNDERSTORMS...AND GUSTY
WINDS ACCOMPANYING THE SURFACE LOW.

&&

.AVIATION...
THE DEEP CONVECTION FOCUSED OVER SOUTHWESTERN PUERTO RICO THIS
AFTERNOON IS BEGINNING TO DISSIPATE TURNING ALL EYES TO THE NEXT
FEATURE COMING IN THURSDAY MORNING. A SURFACE LOW JUST EAST OF THE
LEEWARD ISLANDS WILL TRACK WEST SOUTHWEST ACROSS THE AREA OVER THE
NEXT FEW DAYS. WRAP AROUND BANDS WILL MOVE INTO THE NORTHERN COAST
AND THE U.S.V.I OVERNIGHT AND PROBABLY BEGIN AFFECTING TAF SITES
OF THE VI AND TJSJ BY EARLY MORNING. FOR THE MOMENT...WENT WITH
SHRA MOVING INTO THESE SITES AT 10Z. WILL LET NEXT SHIFT EVALUATE
THE NEED...IF ANY...FOR REDUCED VISIBILITIES AND CEILINGS.

&&

...MARINE...
WINDS AND SEAS WILL BEGIN TO INCREASE OVERNIGHT THROUGH THURSDAY
AND CONTINUE TO DETERIORATE MARINE CONDITIONS THROUGH THE END OF
THE WEEK. THE INCREASING NORTHEAST WIND FLOW WILL CREATE
BUILDING SEAS TO NEAR 9 FEET ACROSS THE OFFSHORE ATLANTIC BY
FRIDAY. EAST NORTHEAST SWELLS WILL BEGIN TO AFFECT THE LOCAL WATERS
THURSDAY AFTERNOON AND CONTINUE INTO THE WEEKEND. SMALL CRAFT
ADVISORIES WILL THEREFORE BE REQUIRED BY THURSDAY AFTERNOON.
HIGH SURF ADVISORIES MAY ALSO BE NECESSARY FOR THE NORTH AND EAST
COASTS BY LATE THURSDAY AND POSSIBLY INTO THE WEEKEND AS A RESULT
OF THE APPROACHING LOW PRESSURE FEATURE.

http://www.srh.noaa.gov/fwd/productview ... &version=0

[cycloneye]

TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
530 PM EDT WED OCT 24 2007

THE LOW PRESSURE AREA CENTERED ABOUT 75 MILES NORTHEAST OF THE
NORTHERN LEEWARD ISLANDS HAS BECOME A LITTLE BETTER DEFINED TODAY.
HOWEVER...THE ASSOCIATED SHOWER ACTIVITY IS POORLY ORGANIZED AND
UPPER-LEVEL WINDS ARE STILL UNFAVORABLE FOR SIGNIFICANT
DEVELOPMENT. THIS SYSTEM IS EXPECTED TO MOVE SLOWLY WESTWARD OR
WEST-SOUTHWESTWARD DURING THE NEXT COUPLE OF DAYS.

$$

FORECASTER BROWN/BEVEN

[Blown Away]

This should be an Invest soon.

[Derek Ortt]

NOGAPS has slightly lower shear than does model NCEP. NCEP has not really had a good handle on this area of low-pressure so far, so I am not that inclined to believe its solution at this time.

[Derek Ortt]

Also, I checked the shear for the canadian solution... it looks like a baroclinic intensification as it mvoes through the Bahamas as the shear is quite strong

[cycloneye]

Antigua Observations



The observations in the island of Antigua show light west winds and pressure of 1009 mbs.

[ronjon]

From HPC Discussion:

...TROPICS...

WE WILL BE WATCHING FOR POSSIBLE TROPICAL DEVELOPMENT IN THE CARIBBEAN SEA DURING THE NEXT SEVERAL DAYS THAT COULD DRIFT NW...THEN N...POSSIBLY AUGMENTING OVERRUNNING PCPN OVER FL NEXT TUE-WED.

[ronjon]

12Z Euro slowly moves this low pressure system west toward the NW caribbean and stalls it for several days between the Cayman Islands and the Yucatan. It eventually moves it N toward the SW FL coast late in the period. Keeps the system fairly weak and broad. If this verifies, there will be a heck of a pressure gradient across the FL peninsula between this low pressure and high pressure off the mid-Atlantic Coast. Euro indicates east winds over the FL peninsula of 25-40 mph for several days late this weekend/early next week.

http://www.ecmwf.int/products/forecasts/d/charts/medium/deterministic/msl_uv850_z500!Wind%20850%20and%20mslp!192!North%20America!pop!od!oper!public_plots!2007102412!!/

[DESTRUCTION5]

From HPC Discussion:

...TROPICS...

WE WILL BE WATCHING FOR POSSIBLE TROPICAL DEVELOPMENT IN THE CARIBBEAN SEA DURING THE NEXT SEVERAL DAYS THAT COULD DRIFT NW...THEN N...POSSIBLY AUGMENTING OVERRUNNING PCPN OVER FL NEXT TUE-WED.

Augmenting...LOL

[cycloneye]

000
ABNT20 KNHC 250206
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1030 PM EDT WED OCT 24 2007

SHOWER AND THUNDERSTORM ACTIVITY ASSOCIATED WITH A LOW PRESSURE
AREA LOCATED JUST NORTHEAST OF THE NORTHERN LEEWARD ISLANDS REMAINS
POORLY ORGANIZED. UPPER-LEVEL WINDS ARE EXPECTED TO REMAIN
UNFAVORABLE FOR SIGNIFICANT DEVELOPMENT OF THIS SYSTEM AS IT MOVES
SLOWLY WESTWARD OR WEST-SOUTHWESTWARD DURING THE NEXT COUPLE OF
DAYS.

$$

FORECASTER BROWN

[boca]

Looking at the satelite picture is that low shaped like a horseshoe and moving eastward or is it the area to the west of that?

http://www.ssd.noaa.gov/goes/east/watl/loop-avn.html

Sorry I'm confused is the low NNE of PR or just east of the Northern Leewards?

[Fego]

From the NWS in San Juan... very interesting.

000
FXCA62 TJSJ 250337
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1137 PM AST WED OCT 24 2007

.UPDATE...THE 00Z SOUNDING SHOWED INCREASED MOISTURE UP THROUGH
500 MB OVER SAN JUAN. A LOW PRESSURE IS SLOWLY DEVELOPING JUST
NORTHEAST OF THE NORTHEASTERN CARIBBEAN. THE STEADY TREND
DOWNWARD OF THE ATMOSPHERIC PRESSURE IN BUOY 41043 ALSO INDICATES
THE PRESENCE OF THIS LOW. LOW LEVEL CIRCULATION IS MASKED FOR THE
MOST PART BY HIGHER LEVEL CLOUDS AND CELL MOVEMENTS TRACKED ON
RADAR SUGGEST SOME CYCLONIC CIRCULATION TO OUR EAST. QUIKSCAT DATA
FOR THE 22Z PASS WAS NOT YET AVAILABLE. MODEL BEHAVIOR HAS BEEN
CONSISTENT IN ONE SENSE AND CHANGING IN ANOTHER. THREE MODELS
CONFIRM THE LOW PRESSURE...UKMET...GFS AND THE NAM. THE NAM IS THE
MOST INTENSE WITH THE DEVELOPMENT AND TAKES THE CENTRAL PRESSURE
FROM 1005 MB 26/03Z TO 1002 MB 26/09Z JUST NORTHEAST OF CABEZAS
DE SAN JUAN...WHICH MEANS THAT IT IS FORECASTING A TROPICAL STORM.
ONLY THE 18Z RUN OF THE GFS IS AVAILABLE AT THIS TIME...AND IT
DOES NOT DEEPEN THE LOW BELOW 1008 MB. BOTH FOLLOW SIMILAR TRACKS AND
BOTH CROSS OVER PUERTO RICO WITH THE LOW. OF COURSE THE NAM HAS
STRONGER WINDS ACCOMPANYING THE LOW PRESSURE...BUT SURFACE WINDS
OVER THE ISLANDS DO NOT INCREASE MUCH UNTIL 26/09Z FOR THE U.S.
VIRGIN ISLANDS AND 26/15Z FOR PUERTO RICO. THE STRONGEST WINDS
INSTEAD ARE DEPICTED NORTH OF THE ISLAND OVER LOCAL ATLANTIC
WATERS AND REACH 40 KNOTS AT 26/21Z JUST NORTH OF AGUADILLA.

IT IS NOT CLEAR WHY THE NAM WANTS TO DEVELOP THIS LOW SO
STRONGLY...ESPECIALLY SINCE UPPER LEVEL WINDS ARE DECIDEDLY
UNFAVORABLE. FIRST A 50 KNOT JET CROSSES THROUGH THE AREA AT 250
MB AND THEN UPPER LEVEL WINDS OVER THE DEVELOPING LOW ARE BETWEEN
15 AND 25 KNOTS...GENERALLY FROM THE NORTHWEST. UPPER LEVEL WINDS
IN THE SOUTHWEST QUADRANT OF THE LOW REACH ALMOST 40 KNOTS ON
FRIDAY. IT IS NOTED THAT ON UPPER LEVEL WINDS...THE NAM AND THE GFS
DIFFER LITTLE. THEREFORE AM NOT ALLOWING THE WIND FORECAST TO
VENTURE MUCH ABOVE 22 TO 25 KNOTS OVER OUTER ATLANTIC WATERS ON
THURSDAY AND FRIDAY. MOISTURE IS GOOD IN BOTH THE GFS AND THE NAM
AND AM FAVORING THE PATTERN PRODUCED BY THE NAM...IN PART BECAUSE
OF THE BETTER RESOLUTION AND IN PART BECAUSE THE DEVELOPMENT OF
THE LOW CIRCULATION SEEMS MORE TRUSTWORTHY IF ONLY QUALITATIVELY.

THE PATTERN AND THE FOCUS OF THE RAIN WILL CHANGE DRASTICALLY ON
THURSDAY IF THE NAM OR THE GFS VERIFY. THAT IS...THE WIND PATTERN
BECOMES NORTHWEST IN THE SOUTHWEST QUADRANT OF THE LOW WHICH IS
OVER PUERTO RICO THURSDAY AFTERNOON...25/18Z...ON ITS CURRENT
PROJECTED TRACK...AND THIS SHOULD TAKE SOME OF THE FOCUS FOR RAIN AWAY
FROM THE NORTHWEST COASTAL REGIONS...AND ADD TO THE SOUTHEAST
INTERIOR REGIONS. THIS IS NOT GOOD NEWS FOR THE WESTERN
INTERIOR...HOWEVER...WHICH ARE BEGINNING TO EXPERIENCE MINOR
MUDSLIDES...SINCE RAIN AMOUNTS EXPECTED ARE STILL EXPECTED TO BE
SIGNIFICANT THERE.

RAIN...THOUGH BY NO MEANS CONTINUOUS...IS EXPECTED TO CONTINUE
INTERMITTENTLY THROUGH THE WEEKEND...WITH BANDS OF SHOWERS
FOCUSING ON MANY PARTS OF PUERTO RICO AND ALSO THE U.S. VIRGIN
ISLANDS...CULEBRA AND VIEQUES. HOW THIS PLAYS OUT WILL DEPEND ON
HOW MUCH THE LOW LEAVING PUERTO RICO AROUND 26/21Z HAS DEVELOPED.
STRONG DEVELOPMENT SHOULD YIELD ONE OR MORE CONVERGENCE BANDS THAT
COULD PRODUCE SIGNIFICANT RAINFALL OVER THE AREA.

THIS PLACES PUERTO RICO AND POSSIBLY THE U.S. VIRGIN ISLANDS AT
SOME RISK FOR URBAN AND SMALL STREAM FLOODING AND MUDSLIDES DURING
THE NEXT FOUR DAYS.

HAVE LEFT THE RE-EVALUATION OF SEAS TO THE NEXT SHIFT. THEY COULD
BE TRICKY DUE TO THE WIDE VARIATION OF WIND ACROSS THE LOCAL AREA.

[Meso]

EURO has it in about the same place as the CMC at around 60 hours,and then the EURO has it moving WSW and then NE


00z CMC (it's the system near the Yucatan)


000
ABNT20 KNHC 250901
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
530 AM EDT THU OCT 25 2007

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

AN AREA OF LOW PRESSURE LOCATED JUST NORTHEAST OF THE NORTHERN
LEEWARD ISLANDS IS PRODUCING A LARGE AREA OF CLOUDINESS AND
SHOWERS. UPPER-LEVEL WINDS ARE EXPECTED TO REMAIN UNFAVORABLE
FOR SIGNIFICANT DEVELOPMENT OF THIS SYSTEM AS IT MOVES SLOWLY
WESTWARD OR WEST-SOUTHWESTWARD DURING THE NEXT COUPLE OF DAYS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$

FORECASTER BROWN

[wxman57]

It certainly doesn't look better organized this morning. Still, something to keep an eye on. But development chances may have diminished.

[cycloneye]

wxman57,it is not organizing now,but we here expect bad weather from today thru the weekend.

000
FXCA62 TJSJ 251015
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
615 AM AST THU OCT 25 2007

.SYNOPSIS...LLVL LOW N OF LEEWARD ISLANDS HAS BECOME AN ELONGATED
CIRCULATION OVERNIGHT...COINCIDENT WITH UPPER LOW LINGERING ACROSS
THE REGION...NEARLY WEST TO EAST ALONG 19.5N BETWEEN 66 AND 57W.
THIS IS PRODUCING CYCLONIC FLOW AT LLVLS ACROSS THE LOCAL
AREA...AND WNW CONVERGENT FLOW ALOFT...WHICH CONTINUES TO
STABILIZE MID LEVELS ACROSS THE NE CARIB.

&&

.DISCUSSION...QUITE AN INTERESTING AND CHALLENGING FORECAST...BUT
LOOKS LIKE UKMET...ECMWF SOLUTIONS OF RECENT DAYS ARE PLAYING OUT.
L/W TROF ACROSS CENTRAL ATLC WILL CONTINUE TO DIG SW THROUGH THE
WEEKEND AND FORCE THE DEEP LAYERED ELONGATED LOW WSW TODAY AND THEN
MORE SW OVERNIGHT THROUGH SATURDAY NIGHT. THE LOW TO MID LEVEL
CIRCULATION WILL EVENTUALLY DETACH AND MOVE ACROSS PR TONIGHT AND
THEN PASS S OF HISPANIOLA FRI THRU SAT NIGHT. STRONG PRESSURE
GRADIENT INDUCED BY LARGE HIGH ACROSS THE W ATLC WILL PRODUCE
STRONG WINDS POTENTIALLY NEARING GALE FORCE ACROSS N QUADS OF LOW
AS IT SHIFTS ACROSS THE AREA...WITH THESE WINDS EXPECTED TO
REMAIN ACROSS THE OFFSHORE ATLC...AND POSSIBLY N MONA PASSAGE.
BEST MOISTURE...AND ASSOCIATED SQUALLS AND TSTORMS WILL MOVE INTO
THE LOCAL ISLANDS LATE THIS AFTERNOON THROUGH SAT...OCCURRING ALL
AROUND THE N AND ERN PERIPHERY OF THE LOW. UPPER LEVEL FLOW IS
EXPECTED TO BECOME MORE NW AND DIVERGENT ACROSS THE AREA BY THIS
AFTERNOON TO CREATE UNSTABLE CONDITIONS ALOFT...THAT WILL LINGER
THROUGH THE ENTIRE WEEKEND. ALTHOUGH LLVL WINDS AND MOISTURE WILL
DECREASE SAT NIGHT AND SUNDAY...ISOLATED AREAS OF DEEP CNVTN WILL
REMAIN POSSIBLE.

SO FOR TODAY...LOOK FOR NNE TO NLY FLOW TO ADVECT NUMEROUS SHOWERS
AND ISOLATED TSTORMS INTO THE LOCAL AREA...WITH DIURNAL FORCING
FOCUSING AFTERNOON ACTIVITY ACROSS THE INTERIOR AND N SLOPES OF
PR...WITH ACTIVITY THEN BECOMING MORE FREQUENT AND POTENTIALLY MORE
INTENSE THIS EVENING THROUGH FRIDAY. RECENT RAINS HAVE LEFT LARGE
AREAS AT OR NEAR SATURATION ACROSS INTERIOR AND W PR...AND
MUDSLIDES WERE REPORTED YESTERDAY IN UTUADO. CONTINUED RAINS
THROUGH THE WEEKEND WILL LIKELY CAUSE FLOODING PROBLEMS ACROSS
PUERTO RICO AND POTENTIAL FOR MUDSLIDES...AND POSSIBLY THE VIRGIN
ISLANDS FRI AND SAT. THIS IS SHAPING UP TO BE THE MOST
SIGNIFICANT RAIN EVENT OF THE FALL WET SEASON THUS FAR...SO LOCAL
INTERESTS AND EMERGENCY MANAGERS KEEP ABREAST OF ENSUING
FORECASTS.


&&

.AVIATION...VFR FLIGHT CONDITIONS ARE EXPECTED ACROSS PONCE AND
MAYAGUEZ THIS MORNING...WHILE THE REST OF THE LOCAL TAF SITES MAY
EXPERIENCE MVFR FROM 12Z TO 15Z ESPECIALLY TJSJ...TJBQ AND TIST.
FOR THIS AFTERNOON THROUGH THIS EVENING CONTINUING INTO
SATURDAY...WE ARE EXPECTING SCATTERED TO NUMEROUS SHOWERS AND
TSTORMS TO AFFECT THE LOCAL ISLANDS MAINLY THE NORTHERN
COASTS...WHERE MOST OF THE TAF SITES ARE LOCATED. HAVING SAID
THAT...PILOT SHOULD MONITOR CLOSELY THE WX CONDITIONS ACROSS THE
LOCAL ISLANDS TODAY THROUGH SATURDAY AS WX CAN RAPIDLY CHANGE
SIGNIFICANTLY WITHIN A FEW HOURS.


&&

.MARINE...LARGE ENE SWELLS HAVE BEEN MOVING INTO REGIONAL WATERS
SINCE YESTERDAY...GENERATED FROM ELY WIND FIELD ACROSS THE TOP OF
ELONGATED LOW AS IT HAS SHIFTED NW PAST DAYS. THESE SWELLS WILL
INCREASE AND BUILD INTO NEAR SHORE ATLC AND MONA PASSAGE
TODAY...AND SCA ARE IN EFFECT FOR LATER TODAY FOR ALL BUT CARIB
WATERS SE THRU SW OF PR. STRONGEST WINDS ASSOCIATED WITH SHIFTING
LOW WILL OCCUR ACROSS THE N PERIPHERY AND ARE EXPECTED TO REMAIN
ACROSS THE FAR OUTER ATLC WATERS AND MONA PASSAGE THIS EVENING
THROUGH EARLY SAT...BUT ANY MORE SW TRAJECTORY OF THIS FEATURE
COULD ALLOW THESE WINDS TO BUILD IN CLOSER TO THE N COASTS.
ASSOCIATED WITH THE STRONGER WINDS...SQUALLS AND TSTORMS WILL BE
CAPABLE OF PRODUCING WIND GUSTS 35 KNOTS AND GREATER. LONGER
PERIOD SWELL FROM NELY FETCH ON W QUAD OF CENTRAL ATLC LOW WILL
BUILD INTO REGIONAL WATERS LATE FRIDAY NIGHT TO MAINTAIN HIGH SEAS
AND ROUGH SURF ATLC COASTS THROUGH THE ENTIRE WEEKEND. A HIGH SURF
ADVISORY WILL BE REQUIRED FOR THIS EVENING FOR ATLC COASTS.

[ronjon]

00Z Euro looking more ominous this morning with the low NE of the LA moving W-SW into the western caribbean sea SW of JAM. Euro now moves it northward from that point while strenghtening the storm off western Cuba and into S FL in the long range.

http://www.ecmwf.int/products/forecasts/d/charts/medium/deterministic/msl_uv850_z500!Wind%20850%20and%20mslp!168!North%20America!pop!od!oper!public_plots!2007102500!!/