Don't believe the models

By: Dr. Jeff Masters , 1:33 PM GMT on September 12, 2005

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Don't believe any of the computer forecast models or the official NHC forecast--no one knows where Ophelia is going. Ophelia is trapped between two large and strong high pressure systems, and will continue to behave unpredictably. The 5am NHC discussion called it this way: "None of the reliable dynamical models have been immune from significant track forecast shifts during the past day or two in this very difficult scenario." In other words, we have no idea where Ophelia is going.

A slow westward drift has been the trend the past day or so, and several of the models show a slow westward or northwestward drift the next two days. Thus, it is reasonable to anticipate that Ophelia's outer rain bands will start to impact the North Carolina and South Carolina coasts this afternoon through tomorrow, bringing localized heavy rain and minor flooding. The usually-reliable GFS model's latest run at 06Z (2am EDT) this morning shows Ophelia hitting Charleston as a strong tropical storm Tuesday morning, and the GFDL thinks Ophelia will be a Category 1 hurricane hitting South Carolina Tuesday night. The other models disagree, letting Ophelia wander off the coast the next two days, and forecast that by Wednesday, a weak trough will push off the East Coast and take Ophelia northward across eastern North Carolina and out to sea. However, the models have trended towards making this trough weaker and weaker. There now appears to be a significant possibility that the trough will fail to pick up Ophelia, high pressure will build back in, and she will wander around the ocean waters near Cape Hatteras for a few more days. The Canadian model has a rather omininous solution--the high pressure that builds in will be strong enough to push Ophelia southwestward, across northern Florida, and into the Gulf of Mexico five days from now. I pooh-poohed this solution when I saw it yesterday, but now this forecast cannot be discounted. The Canadian model has been suggesting that the trough would fail to pick up Ophelia for three runs in a row now, and the NOGAPS and UKMET are starting to show the same thing. In any case, none of these models should be taken very seriously; this is an extremely difficult forecast situation, and trying to predict what Ophelia will do five days from now, let alone tomorrow, will involve more luck than skill.

Intensity forecast
The latest hurricane hunter mission was at 8:30am EDT, and showed a slightly weaker storm with a poorly-formed eyewall, a central pressure of 988 mb, and peak winds of just 48 knots on the west side. The crew will find stronger winds once they penetrate the north eyewall where the strongest winds are, but Ophelia might get downgraded to a tropical storm today.


Figure 1. Surface winds in Ophelia yesterday afternoon as seen from the NOAA hurricane hunter aircraft.

Dry air continues to be Ophelia's bane; a large amount of it has wrapped into the core of the hurricane and disrupted the convection on the west side. There is still plenty of dry air on her northwest side, and this should continue to be a problem for her the next few days. Cold water stirred up from down deep by Ophelia's winds will also continue to be a problem as she wanders over the same ocean area for multiple days. On the plus side for intensification, wind shear remains lows, about 5 - 10 knots out of the northwest. The upper-level ouflow pattern remains good, and the overall organization of Ophelia is strong. Given all these factors, neither significant strengthening or weakening is likely the next two or three days, and Ophelia will remain a strong tropical storm or weak Category 1 hurricane during this period.

Elsewhere in the tropics
Nothing is going on. Large amounts of dry, dust-laden Saharan air cover most of the tropical Atlantic including the Caribbean Sea.

Jeff Masters

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273. WillJax
9:38 PM GMT on September 12, 2005
Even a weak storm will produce torential rains, and the strong gusts will certainly knock down some trees.

All sources say NW 3mph... think this is it, the final leg until landfall??
Member Since: September 7, 2005 Posts: 0 Comments: 33
272. HillsboroughBay
9:29 PM GMT on September 12, 2005
Urgent as storm moves onshore!
Things to Know BEFORE A HURRICANE THREATENS…
Elevation Of Your Home Above Sea Level
Get this information from the office of the Emergency Management Coordinator (EMC). Your nearest Weather Service office can supply flood-stage data for area streams and waterways. Find out if your home is subject to storm surge (tidal) flooding.
Maximum Storm Surge Which Might Occur
Information about the potential for inland flooding and storm surge is available through your local EMC or website.
Route To Safety If You Have To Leave
Plan your escape route early. Check with your local Emergency Managment Center or web site for low points and flooding history of your route.
Check the number of hours it could take you to evacuate to a safe area during peak evacuation traffic.

For the “members” who think that this message is not appropriate please ignore it.
As this is a Public forum sponsored By Dr. Masters it is not the specific property nor is it under the control of any group.
There are many members who do not spend 18 hours per day following a specific weather system. We recently have had a severe loss of life just because many did not know what to do because their local agency did NOT warn them.
While it is understood that some members are interested in traveling to where the system may make landfall, you must try & understand that many more people just stop by & read posts. If the fact that some warnings are posted a few times per day/ new Blogg we apologize. However there are people who need to see these messages. If you must be Rude, and or childish please do it in you own blogg. Hourly messages were not posted. The heading was just because the weather system started to move
271. VerticalHeatEngine
8:58 PM GMT on September 12, 2005
NHC has her at 3 mph.
270. rescueguy
8:54 PM GMT on September 12, 2005
5pm advisory still has her moving north west at 5mph, iam not buying it!
Member Since: September 12, 2005 Posts: 0 Comments: 128
269. VerticalHeatEngine
8:45 PM GMT on September 12, 2005
Hi rescue. Here in Horry county (MB) there is a voluntary evac. No school tomorrow.

Local wx guy on wpde says its going to the obx and that we shouldn't worry!!!

More importantly, I just came in from securing my dish and the ants were crawling up the sides of the house. So, forget the models, the ants have spoken!!! Ms. O is coming! lol
268. HurricaneZane
8:42 PM GMT on September 12, 2005
thanks iyou!
267. killdevilmax
8:40 PM GMT on September 12, 2005
New thread Dr.Masters update. Looks she she's not going to make a turn yet.
Member Since: August 28, 2005 Posts: 0 Comments: 322
266. CoastalNC
8:39 PM GMT on September 12, 2005
As soon as she makes landfall, I think she'll just seriously fall apart. She has barely held it together so far anyway.

265. AySz88
8:38 PM GMT on September 12, 2005
How do troughs and ridges effect the system? The system moves toward troughs and away from ridges?
Member Since: August 25, 2005 Posts: 0 Comments: 8
264. GZ
8:33 PM GMT on September 12, 2005
good call rebel. If we have a TS over of heads for two days she will do some serious damage!
263. rescueguy
8:33 PM GMT on September 12, 2005
here in charleston its just another typical monday, nobody is really aware of the storm they all just think its going up north. Anybody from horry county online here, what are they saying up there? Same ole stuff, going out to the obx
Member Since: September 12, 2005 Posts: 0 Comments: 128
262. WeathermanBob
8:30 PM GMT on September 12, 2005
RescueGuy...local guys here (Aiken, SC) are following script from NHC and TWC.
261. leftyy420
8:30 PM GMT on September 12, 2005
even then they just say oh its just a cat1 lol
Member Since: August 24, 2005 Posts: 35 Comments: 1987
260. NCRebel
8:27 PM GMT on September 12, 2005
Was just looking a the Visible loop on the NHC website with MSLP. The pressures north of O appear to be dropping. i guess this is why she's moving. Or maybe she's trying to show the high to the north who's boss. On several loops it's obvious she's clsoing her corculation and with her moving towards warmer water there is no telling what could happen.
My wife just came in and asked about it. I told her it was a TS and she was like oh no big deal then. Jeesh how do you make people understand that the only different between a TS and a CAT 1 is 1 MPH.
259. iyou
8:24 PM GMT on September 12, 2005
HurricaneZane - you can find info about dust, particles etc. here - http://science.nasa.gov/headlines/y2001/ast26jun_1.htm
Member Since: July 25, 2005 Posts: 0 Comments: 5219
258. rescueguy
8:24 PM GMT on September 12, 2005
weatherman bob, are you from charleston and if so what are the local guys saying? I am stuck at work but our emergency management people havent said a thing all day.
Member Since: September 12, 2005 Posts: 0 Comments: 128
257. GZ
8:24 PM GMT on September 12, 2005
thanks lefty!
256. leftyy420
8:14 PM GMT on September 12, 2005
yes very littlemovement. no one knows where she is going g so we ahve to wait and see
Member Since: August 24, 2005 Posts: 35 Comments: 1987
255. leftyy420
8:13 PM GMT on September 12, 2005
ok just checked some bouys and the sea temps to her wes ad w ar 80-82 degress. thepressure 90 milesform the cenetr is anywehre from 1015-1009 so gives u an idea of how low ur pressur ewill get and the closer to the cenetr the fastr it droips, currently 989 at the center

now with those warm waters ahead of her and the dry air being mixed out we might see her ramp up a little over the next 12-24 hrs
Member Since: August 24, 2005 Posts: 35 Comments: 1987
254. WeathermanBob
8:13 PM GMT on September 12, 2005
NEWS FLASH...O is heading due west! Charleston get prepared for a visit from O and hopefully Steph!!!
253. GZ
8:13 PM GMT on September 12, 2005
just got home from work. can someone update me? what are looking at in Wilmington? Is she going to hang over our heads the next two days?
252. NCRebel
8:13 PM GMT on September 12, 2005
Anyone considered that maybe they sent Cantore to a zone that may not have much impact? I mean come on the poor guy needs break. LOL
251. HurricaneZane
8:13 PM GMT on September 12, 2005
thanks guys. I love how friendly everyone is here. I don't care what the others say about you --hehe ; )
250. butterflymcb
8:11 PM GMT on September 12, 2005
Those around Cantore better board up some windows...lol
Member Since: August 25, 2005 Posts: 0 Comments: 38
249. thelmores
8:11 PM GMT on September 12, 2005
i see very little northern movement at all, but i definately see a westward movement.....

i think the next forecast track will be much farther to the left, much as the gfdl model indicated.

If this storm is gonna turn nw and n, it better hurry, or it's gonna run into the grand strand!
Member Since: September 8, 2005 Posts: 0 Comments: 3805
248. NCRebel
8:10 PM GMT on September 12, 2005
Well she's moving alright. Is it just me or is she closing her south end too. She should be getting pretty clost to the Gulf Stream so any strengthening would need to occur soon. Just my opinion.
247. cgableshurrycanegal
8:10 PM GMT on September 12, 2005
it also depends on whether or not there has been serious drought on the continent. It will disrupt cyclonic formation. As to comparing this year to others, good question, first time I've been aware of it as such a player
Member Since: July 12, 2005 Posts: 24 Comments: 212
246. leftyy420
8:08 PM GMT on September 12, 2005
well africa is a dessert lol. actually africa is going thru a drought so alot more dust thjan usual is being picked up by strein winds and blown off the coast. sandstorms basically. this sand than can float in the air all the way to the easter us coast if the winds are strong enough. it happens every year but this year it is worse than i ahve seen in a few years
Member Since: August 24, 2005 Posts: 35 Comments: 1987
245. cgableshurrycanegal
8:08 PM GMT on September 12, 2005
Saharan dust always blows off the Continent, some years more than others. It also blows into diff parts of the ATL more than others. I remember year after year in Puerto Rico with brassy skies due to it, inhibits rainfall and creates horrible dusty and dry conditions.
Member Since: July 12, 2005 Posts: 24 Comments: 212
244. EllistonVA
8:06 PM GMT on September 12, 2005
Ophelia finally starts moving and our air gets drier than ever. We started out the day at 32% humidity, we're down to 25% now. Someone please push her this way! Nothing major, nothing to hurt anybody, just a nice solid soaking of some very parched Virginians!
Member Since: May 3, 2002 Posts: 0 Comments: 0
243. cgableshurrycanegal
8:05 PM GMT on September 12, 2005
STOP THE PRESSES!!!

TWC is taking this very seriously!!!
They have Jim Cantore at Nags Head!!!
They have Jeff Morrow at Wrightsville Beach!!!
Member Since: July 12, 2005 Posts: 24 Comments: 212
242. HurricaneZane
8:05 PM GMT on September 12, 2005
I have a question about African dust...what is it? , and is it usual during hurricane season, or is this a year where there has been more then usual.

I have never heard of it before this year.. of course I am kind of new to this whole thing.. I didn't really think about cyclones up in NY. (although I DO remember getting some of David in 79'--I was only 6 though..)
241. leftyy420
8:02 PM GMT on September 12, 2005
that rainband offshore is the leading edge of the ts force winds. also dopler has indicated there are gusts in those bands as high as 50+ mph
Member Since: August 24, 2005 Posts: 35 Comments: 1987
240. thelmores
8:01 PM GMT on September 12, 2005
the barometer continues to drop here in myrtle beach....

was 30.05" when i came in at 8am this morning, we are down to 29.94", and still dropping!
Member Since: September 8, 2005 Posts: 0 Comments: 3805
239. VerticalHeatEngine
8:01 PM GMT on September 12, 2005
Thelmores, looks like we are almost in range of trop storm force winds according to the latest wind profile.

We still have sun peaking through. Wind is still a steady 20 with about 30 mph gusts. Pressure down to 1010.7 mb. Otherwise, nothing significant going on at the beach.
238. leftyy420
7:53 PM GMT on September 12, 2005
lol yeah
Member Since: August 24, 2005 Posts: 35 Comments: 1987
237. thelmores
7:52 PM GMT on September 12, 2005
I am starting to think lanfall around the nc/sc border is looking pretty solid!

this storm has definately traveled much faster to the west than the nhc thought..... course with this freakin storm, throw the model consensus out!!!!!!
Member Since: September 8, 2005 Posts: 0 Comments: 3805
236. leftyy420
7:50 PM GMT on September 12, 2005
new vortex is out. pressure is still 989 but on this pass the highest flright level winds recorded was 55kts. they might drop her intensity down to 60-65 mph but we will see


URNT12 KNHC 121944
VORTEX DATA MESSAGE
A. 12/17:19:30Z
B. 31 deg 42 min N
077 deg 16 min W
C. 700 mb 2985 m
D. 50 kt
E. 135 deg 073 nm
F. 221 deg 055 kt
G. 135 deg 082 nm
H. 989 mb
I. 9 C/ 3026 m
J. 12 C/ 3047 m
K. NA C/ NA
L. NA
M. NA
N. 12345/ 7
O. 0.05 / 1 nm
P. AF300 1816A OPHELIA OB 29
MAX FL WIND 69 KT NW QUAD 13:27:00 Z

Member Since: August 24, 2005 Posts: 35 Comments: 1987
235. pirateotobx
7:47 PM GMT on September 12, 2005
Ophelia is definitely on the move..she may have finally decided to do something....she's definitely moving faster than most models were figuring on...Ophelia is bound and determined to keep everyone guessing..
234. leftyy420
7:47 PM GMT on September 12, 2005
but itsnot needed and its kinda stupid to keepposting it. everyone from florida to va who is in this blog is watching the storm.
Member Since: August 24, 2005 Posts: 35 Comments: 1987
233. FLCrackerGirl
7:45 PM GMT on September 12, 2005
Hills, I & others, just want folks to be vigilant... Things can change quickly, Being Prepared can't be overstated enough.

(i do in fact have a life... REFRESH, Copy, Paste & Post is not real tough.)
Member Since: August 12, 2004 Posts: 47 Comments: 597
232. cgableshurrycanegal
7:45 PM GMT on September 12, 2005
LOL... now wunderyakuza will boot us both!!! nah, he's a good guy, knows we need breaks from Oph.

From reading Steve's Blog I think Oph might come in sooner than later, what do you think?
Member Since: July 12, 2005 Posts: 24 Comments: 212
231. leftyy420
7:44 PM GMT on September 12, 2005
sorry cgb i was getting a second source befor i stated it lol
Member Since: August 24, 2005 Posts: 35 Comments: 1987
230. leftyy420
7:42 PM GMT on September 12, 2005
yeash i watched that on tv as well and looked it up ongoogle befor i posted. wow. now maybe we can start to get somewhere in this country
Member Since: August 24, 2005 Posts: 35 Comments: 1987
229. cgableshurrycanegal
7:42 PM GMT on September 12, 2005
AHA!!! I beat you lefty!!! nyah nyah!!!
Member Since: July 12, 2005 Posts: 24 Comments: 212
228. leftyy420
7:41 PM GMT on September 12, 2005
wow fema director mike brown resigned today
Member Since: August 24, 2005 Posts: 35 Comments: 1987
227. cgableshurrycanegal
7:41 PM GMT on September 12, 2005
quick political break!
STOP THE PRESSES!!!
Local FOX - CNN affiliate says Brownie resigned from FEMA
Member Since: July 12, 2005 Posts: 24 Comments: 212
226. peebswear
7:39 PM GMT on September 12, 2005
I noticed that most the computer models are older vs the Bamm one. Any clue when there will be newer ones? Just concerned with the possibility of a SC landfall and local news is telling us no worries, but I'm not so sure yet.
225. pirateotobx
7:39 PM GMT on September 12, 2005
l8r...;-)
224. leftyy420
7:38 PM GMT on September 12, 2005
bye stormy
Member Since: August 24, 2005 Posts: 35 Comments: 1987

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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