Arthur's remnents near the BOC

[JonathanBelles]

CIMSS Also has their 3D loop of Arthur up now if anyone is interested.

[cycloneye]

A closeup view.

[KWT]

Sorry StormspinnerD2 I meant excuse me if 'I' was a little out of line for that statement, I didn't mean you!

Anyway Arthur looks ok, can clearly see the circulation area still though it is a little on the broad side, though that will probably help it if anything I suspect. Will be interesting to see whether it can keep decent strength overland, if it can stay above say 30kt then it may well re-develop well over the BoC if it makes it.

[Matt-hurricanewatcher]

Yep StormspinnerD2 as the others said it does clearly have a LLC and with winds being found above TS strength and so it was upgraded, nothing more too it then that really!
I think your just trying to save face for dismissing it this morning...excuse me if that was a little out of line.

At the time I saw nothing but broad rotation on visible satellite, and nothing discernible on the microwave imagery. I provided evidence to refute NHC's reasoning for the upgrade (lack of TS force winds from the sources they described). Don't accuse me of being out of line; I have provided valid evidence to my opinion.

Yep StormspinnerD2 as the others said it does clearly have a LLC and with winds being found above TS strength and so it was upgraded, nothing more too it then that really!
I think your just trying to save face for dismissing it this morning...excuse me if that was a little out of line.

At the time I saw nothing but broad rotation on visible satellite, and nothing discernible on the microwave imagery. I provided evidence to refute NHC's reasoning for the upgrade (lack of TS force winds from the sources they described). Don't accuse me of being out of line; I have provided valid evidence to my opinion.

As someone that likes to go against the nhc this is one time I will stick up for them. The system had a clearly defined LLC since yesterday on both buoys' and land obs'. Also this morning a "ob" inland over Belize shown a southwest wind that is the weakest quad of a tropical cyclone my friend. Satellite shown a well defined LLC with banding forming 12+ hours ago. I would of upgraded it 12 hours ago if I was in charge. The system was every bit as developed as Arlene and Alison when it was upgraded. The LLC is clearly trackable even so maybe a little elongated south to north; that won't change the fact that it is closed.

What data do you have to support what you are saying? There is some people that would not like a system to be upgraded with out a eye it seems to me.

[CrazyC83]

Based on the satellite trends, I think the TCR will find Arthur was born at 1200Z (8 am EDT), but it is possible it was a tropical depression as far back as 0600Z (2 am EDT).

[gatorcane]

Derek yes the monsoon trough is in the NW Caribbean which is not good. Even when Arthur moves west I'm wondering if anything else will spin up over the NW Caribbean because it doesn't appear the convection is leaving it anytime soon.

[KWT]

Yeah I agree crazy this morning it was given a rating of 1.5 which I believe is high enough if a closed low is in evidence which it appears it was for a upgrade to TD.
I agree Matt, there was also a ship report with a 44mph wind sustained earlier today if I remember correctly from that region?

[StormspinnerD2]

Someone already posted the link.

http://www.ndbc.noaa.gov/station_page.p ... t=E&tz=STN

Nothing higher than 29 kt. Click the link atop that page for ship reports, none of which are higher than that.

ASCAT:

[KWT]

Its interesting but clearly the only data that is on that page is the once hour readings, the NHc will likely have far more frequant updates and its tiotally possible that within that period a wind speed of say 33-34kts wqas recorded which given the other reports from what I've heard may have been enough for it being upgraded...in the end they probably have more data to look at then us.

[Matt-hurricanewatcher]

Someone already posted the link.

http://www.ndbc.noaa.gov/station_page.p ... t=E&tz=STN

Nothing higher than 29 kt. Click the link atop that page for ship reports, none of which are higher than that.

ASCAT:

I don't "trust" the quickscat to show max winds, on the other hand, I believe I seen some 35-40 mph winds yesterday and late evening posted here. Also that shows clearly that there was a clear south and southeast winds on the southeast quad; besides that is only a few "bars" and most of the area was missed in that quickscat. Meaning its incomplete, so not nearly enough data points to make a judgment based on it.

[StormspinnerD2]

Everything was missed by QuikSCAT, I didn't mean to mention it. QuikSCAT hasn't been updating today. The reason there's only one or two barbs down there is because Arthur was over land when ASCAT passed over it. Scatterometers do not work on land as they require movement of water to take wind measurements. At any rate, I gave you all the surface obs I could find, and nothing supports tropical storm force winds.

[Ivanhater]

Well...i was just checking the nws and saw a tropical storm warning in the central gulf and said excuse me??? Pro mets on here do a wonderful job, but I remember wxman yesterday saying about a zero chance of this developing..no fault to them, this is kind of a crazy setup.

[KWT]

Yeah thats fair enough obviously Ascat wasn't going to be able to get many barbs given it was over land at the time. As for the real obs, as I said before we probably don't get all the raw obs so we have no idea whether there was a sustained period that at least came close enough to 35kts to justify it being upgraded.

[JonathanBelles]

Well...i was just checking the nws and saw a tropical storm warning in the central gulf and said excuse me??? Pro mets on here do a wonderful job, but I remember wxman yesterday saying about a zero chance of this developing..no fault to them, this is kind of a crazy setup.

I saw that warning earlier, and was confused.

[Derek Ortt]

That pass you showed shows a tropical cyclone.

Also, ASCAT has a horrific low bias

[cycloneye]

WTNT31 KNHC 312039
TCPAT1
BULLETIN
TROPICAL STORM ARTHUR ADVISORY NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012008
500 PM EDT SAT MAY 31 2008

...ARTHUR MOVING SLOWLY OVER YUCATAN...

A TROPICAL STORM WARNING REMAINS IN EFFECT FOR THE COAST OF BELIZE
AND FOR THE COAST OF YUCATAN FROM CABO CATOCHE SOUTHWARD TO THE
BORDER WITH BELIZE.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 500 PM EDT...2100Z...THE CENTER OF TROPICAL STORM ARTHUR WAS
LOCATED NEAR LATITUDE 18.4 NORTH...LONGITUDE 88.9 WEST OR ABOUT 75
MILES...125 KM...NORTHWEST OF BELIZE CITY AND ABOUT 195 MILES...315
KM...SOUTHWEST OF COZUMEL MEXICO.

ARTHUR IS MOVING TOWARD THE WEST-NORTHWEST NEAR 7 MPH...11 KM/HR...
AND A GRADUAL TURN TOWARD THE WEST IS EXPECTED TOMORROW. ON THIS
TRACK...THE CENTER OF ARTHUR COULD EMERGE OVER THE BAY OF CAMPECHE
SUNDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS MAINLY OVER WATER EAST OF THE CENTER. ARTHUR IS EXPECTED TO
WEAKEN TO A DEPRESSION TONIGHT...BUT IT COULD THEN REGAIN TROPICAL
STORM STRENGTH IF IT EMERGES OVER THE BAY OF CAMPECHE.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 260 MILES...415 KM
TO THE EAST OF THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.

ARTHUR IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 5 TO 10
INCHES OVER PORTIONS OF BELIZE...GUATEMALA...AND THE YUCATAN
PENINSULA WITH ISOLATED AMOUNTS UP TO 15 INCHES. THESE RAINS COULD
CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES...ESPECIALLY IN
MOUNTAINOUS TERRAIN.

REPEATING THE 500 PM EDT POSITION...18.4 N...88.9 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 7 MPH. MAXIMUM SUSTAINED WINDS...40
MPH. MINIMUM CENTRAL PRESSURE...1005 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 800 PM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 1100
PM EDT.

$$
FORECASTER AVILA/RHOME

000
WTNT41 KNHC 312044
TCDAT1
TROPICAL STORM ARTHUR DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012008
500 PM EDT SAT MAY 31 2008

ARTHUR REMAINS FAIRLY WELL-ORGANIZED ON VISIBLE SATELLITE IMAGERY
DESPITE BEING CENTERED OVER LAND FOR SEVERAL HOURS. ARTHUR HAS A
LARGE LOW-LEVEL CIRCULATION WITH PLENTY OF CONVECTIVE BANDS OVER
THE NORTHWESTERN CARIBBEAN WATERS WHERE MOST OF THE TROPICAL STORM
FORCE WINDS ARE OCCURRING. IN ADDITION...NEW CONVECTIVE CELLS ARE
DEVELOPING OVER THE YUCATAN PENINSULA. BASED ON THE CLOUD PATTERN
ARTHUR IS KEPT AS A 35-KT TROPICAL STORM AT THIS TIME...BUT
WEAKENING IS ANTICIPATED TONIGHT AS THE CENTER MOVES FARTHER
INLAND. THERE IS SOME POTENTIAL FOR SLIGHT INTENSIFICATION IF THE
CENTER MOVES OVER THE BAY OF CAMPECHE.

ARTHUR IS MOVING TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 6
KNOTS. A HIGH PRESSURE SYSTEM OVER THE GULF OF MEXICO WILL KEEP
THE CYCLONE MOVING GENERALLY WESTWARD OVER THE SOUTHERN BAY OF
CAMPECHE OR EVEN INLAND OVER MEXICO. THIS IS CONSISTENT WITH
DYNAMICAL GUIDANCE WHICH UNANIMOUSLY KEEPS THE CYCLONE TRAPPED NEAR
OR OVER THE BAY OF CAMPECHE AND EVENTUALLY DISSIPATES THE CYCLONE
OVER SOUTHERN MEXICO.

FORECAST POSITIONS AND MAX WINDS

INITIAL 31/2100Z 18.4N 88.9W 35 KT
12HR VT 01/0600Z 18.7N 90.0W 30 KT...INLAND
24HR VT 01/1800Z 19.0N 91.5W 30 KT...OVER WATER
36HR VT 02/0600Z 19.0N 93.0W 30 KT
48HR VT 02/1800Z 19.0N 94.5W 35 KT
72HR VT 03/1800Z 18.5N 96.0W 35 KT...INLAND
96HR VT 04/1800Z 18.0N 97.0W 20 KT...INLAND
120HR VT 05/1800Z...DISSIPATED

$$
FORECASTER AVILA/RHOME

[Stratosphere747]

Not sure why everyone is "shocked" by the upgrade. So it's over land as noted by the disco.

Keep in mind that there is a new NHC director on board....

They issued an STDS at 11:30am saying it moved inland already and they didn't expect any significant development today. How would you expect an upgrade to TS a hour and half later?

Because as I've already alluded to, there is a new "chief" on board and there obviously have been some changes. The STDS has no bearing on a upgrade if in fact there is data or observations that come in to warrant it. It's a rather fluid situation as I'm sure you can imagine. The assumption by most everyone was because how things were handled in the past that there wasn't a chance for an upgrade until it emerged in the BOC.

This could be new policy set forth by Bill Read and is only speculation on my part....

[KWT]

Yeah thats true Derek, as you say you can clearly see the way the arrows would point in the direction you'd expect.

Anyway advisory keeps TS Arthur at 40mph, I' still partly amazed by the fact it was a TS in the first place when I came back from work, I doubt it will be the first time I'll be shocked though!

[CrazyC83]

Maybe Arthur was a bit stronger than 35 kt at landfall?

[Brent]

Derek yes the monsoon trough is in the NW Caribbean which is not good. Even when Arthur moves west I'm wondering if anything else will spin up over the NW Caribbean because it doesn't appear the convection is leaving it anytime soon.

This was from a local TV station's blog earlier today:

However, the region from the southern Gulf back into the northwestern Caribbean will remain on the nervous side this week.