ATL: HERMINE - Models

[tolakram]

18Z HWRF

[sponger]

968! Ouch!

[drewschmaltz]

I noticed it still takes HWRF 18 hours from now to gain any latitude and/or drop pressure.

[frederic79]

I'm posting this purely for entertainment purposes, but here's what happened in 1985. The trough was actually split by Hurricane Elena, according to this report. Instead of pulling Elena across Florida as forecast, it stalled Elena allowing a ridge to build back in and push it WNW. Pretty sure things are much different with TD9...


[i]After passing north of Havana, Cuba, Elena emerged into the Gulf of Mexico. At 12:00 UTC on August 29, Elena intensified into a Category 1 hurricane.[3] Analysis of steering currents through the morning of August 30 suggested that Elena would continue on its northwestward track, striking the area between New Orleans, Louisiana, and Biloxi, Mississippi within 30 hours.[4] Unexpectedly, a mid-to-upper-level trough of low pressure diving in from the northwest created a weakness in the easterly currents, allowing Elena to recurve and slow drastically in forward speed.[2][5] Roughly 24 hours after attaining hurricane intensity, the storm abruptly turned east in response to the trough.[2] Having defied initial forecasts, Hurricane Elena drifted on its new course toward the coast of northwest Florida. Forecasters now called for the trough to direct the hurricane across the Florida Peninsula and into the western Atlantic. However, the relatively weak trough moved rapidly, and instead of fully engaging Elena, its axis passed over the storm's center. Further, post-storm analysis of water vapor imagery suggested that the hurricane split the trough into two distinct segments.[4]

Geopotential height chart for the 500-millibar level, showing Elena (the closed isohypse over the Gulf of Mexico) on August 30. The trough that turned Elena toward the east can be seen embedded within the flow over the United States, and the ridge responsible for eventually pushing the storm back is denoted to the east of Florida.
Extrapolation from the storm's eastward progress yielded a projected landfall location near Levy County.[6] However, after the passage of the upper-level system early on August 31, steering currents slackened, and Elena became nearly stationary in the extreme northeastern Gulf of Mexico. At its closest, the center of the storm was around 50 mi (80 km) from Cedar Key, Florida,[2][5] with maximum sustained winds estimated at 105 mph (170 km/h).[7] Elena's intensity remained consistent, and the cyclone was able to continue strengthening as soon as movement resumed. Early on September 1, Elena reached Category 3 major hurricane status.[3] An area of high pressure soon began to build over the eastern United States, causing Elena to slowly retrograde westward.[7][/i] Elena made landfall in coastal Mississippi.

Again, just for entertainment...

[caneman]

I remember it vividly. I lived in the Tampa Bay area at the time. Still do.

[Agua]

Oh yeah, will never forget. Wife and I were very poor living in central Mississippi. Had no TV at the time. Decided to get up early the morning before landfall and drive to FL Panhandle and camp out around Destin. Had no idea the storm was anywhere. Turned on the radio shortly after getting on the road and heard about the storm. CRAP!! "Well, let's go to Dauphin Island instead". We're on US 98 between H'Burg and Mobile at the time and hear an update that it's going in around Orange Beach. "CRAP!" We decide, "damn it!, well let's just go to Biloxi". Take 67 south off of US 98 and get somewhere in Jackson County and hear it's headed towards Biloxi. "CRAP!!" We end up eating dinner at Baricev's on the beach, the last night it was open, then head back north up 49 in the horrendous traffic.

So, will never forget Elena.

[robbielyn]

I remember it well. I was only 19. I lived in lynn haven, fl, near panama city, fl. We decided to evacuate to a shelter which our congregation at that time used our place of worship as a shelter at the time then left cuz it took an eastward turn toward tampa area to have to go to shelter again when it came back west again.Thanks for going down memory lane.

[Alyono]

MU back to insisting this weakens as it moves toward Florida

[StormHunter72]

I remember Elena. Totally different setup though.

[Alyono]

all models trending significantly weaker so far. UKMET, MU, and CMC

Many are also developing another named storm off of the East Coast ahead of this, which makes me suspicious

[RL3AO]

all models trending significantly weaker so far. UKMET, MU, and CMC

Many are also developing another named storm off of the East Coast ahead of this, which makes me suspicious

I've seen a few runs now hinting at some kind of low developing on the northern end of the trough over Florida.

[Alyono]

MU blowing this up into cat 2 east of NC and hooking it toward NYC

[terrapintransit]

Models definitely trending west... Heads up for the entire east coast now

[Hurricane Andrew]

4km NAM brings this to 960 in 24 hours...lol

[caneman]

Models definitely trending west... Heads up for the entire east coast now

My understanding is only in the short term and that long range hasn't changed?

[Recurve]

If I'm getting it right, HWRF is still kind of blowing this up, but on the NHC track. While the official forecast is quite sure that dry air and continuing shear will limit it to less than hurricane strength at first landfall near, uh Steinhatchee I guess. Isn't the HRWF supposed to be skilled at dynamics? I trust the scientists at NHC more than a computer, I'm just wondering what they are seeing and what that model is missing...and are all the other models in consensus on little strengthening?

[N2FSU]

4km NAM brings this to 960 in 24 hours...lol

And a Cat 4 off Apalachicola in 60 hours. Very entertaining! LOL

[drewschmaltz]

If I'm getting it right, HWRF is still kind of blowing this up, but on the NHC track

No, the 06z HWRF just brought it in on the forecast track at 990mb. Shows little to no development for the next 24 hours and barely gets anything going. Pretty realistic solution compared to what we've seen the past 48 hours frm the HWRF.

[drewschmaltz]

4km NAM brings this to 960 in 24 hours...lol

And a Cat 4 off Apalachicola in 60 hours. Very entertaining! LOL

Switching places with the HWRF. I think we'll know in 24 hours who's who as far as the intensity forecast.

[Alyono]

why do I get the feeling that the 4km NAM uses paramaterized convetion...

If it does, the model should have its computer code erased as it is beyond non physical