CrazyC83's Helene Forecast #19 - Drastic change - out to sea

[Derek Ortt]

guys


as i said in the other thread, a weaker trough means a much higher chance of out to sea than a stronger one. The stronger trough is more amplified and could be nagatively titled resulting in a S to N or SSE to NNW track, while the weaker trough has a more zonal flow, meaning a SW to NE track

The weaker trough, unless it ends up near 40N, means bye bye Helene

[Robjohn53]

I sure hope this is right i hate them arrows pointing towards Florida. We just don't need that thing at all. Everything looks good as far as going northward so i hope it will continue to keep on track. Things have been so good this year and that makes me alittle on edge. Just hope everyones luck holds out.

[CrazyC83]

Hurricane Helene Prediction #14

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

Helene went into rapid intensification overnight and has jumped enormously in intensity while maintaining a large, open eye. Dvorak estimates show a range of values as high as 108 kt. I will increase the initial intensity to 100 kt - although higher than the NHC, it seems like my best estimate.

With shear still low and water temperatures still very warm, there is a good chance for additional strengthening. I still easily see Helene becoming a Category 4 hurricane before levelling off and eventually weakening gradually with eyewall replacement cycles and increased shear. The general movement of WNW to NW should continue for the next 72 hours - after that it is either due north or due west then northwest depending on what happens with the ridge. I suspect it will close up and force Helene west then northwest.



Current - 20.5/49.0 - 962mb - 115mph
12 hrs - 21.3/50.3 - 960mb - 115mph
24 hrs - 22.0/51.6 - 952mb - 125mph
36 hrs - 22.7/52.9 - 946mb - 135mph
48 hrs - 23.5/54.4 - 938mb - 145mph
60 hrs - 23.8/56.3 - 934mb - 145mph
72 hrs - 24.0/58.1 - 937mb - 140mph
96 hrs - 24.6/62.3 - 941mb - 135mph
120 hrs - 26.5/65.4 - 946mb - 125mph

[CrazyC83]

Hurricane Helene Prediction #15

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

The rapid intensification trend this morning has levelled off. There are numerous conflicting signs with Helene on both the wind and pressure front. A NOAA research plane went into Helene and found winds of up to 90 kt and a 970mb pressure in the very large eye. On the other hand, satellite estimates suggest winds as high as 115 kt with a 949mb pressure. Since there is nothing conclusive, the initial intensity is held at 100 kt.

There is little change to the track. I am holding on the northwest trajectory before the ridge cuts off Helene and forces it westward. The water remains warm and shear should stay low for the next few days before becoming an issue. There is nothing that can really prevent Helene from becoming a very severe hurricane - easily reaching Category 4. While Category 5 is definitely a stretch, there may be enough of a window to reach that intensity, most likely in the 48-60 hour period before shear increases to weaken Helene. For now, I think 130 kt will be the peak.



Current - 21.1/49.1 - 962mb - 115mph
12 hrs - 22.3/50.2 - 956mb - 120mph
24 hrs - 23.0/51.4 - 951mb - 125mph
36 hrs - 23.9/52.4 - 941mb - 140mph
48 hrs - 24.5/54.3 - 932mb - 150mph
60 hrs - 24.7/56.6 - 936mb - 145mph
72 hrs - 25.0/58.4 - 938mb - 140mph
96 hrs - 25.6/62.4 - 943mb - 125mph
120 hrs - 26.8/65.5 - 945mb - 125mph

[CrazyC83]

Hurricane Helene Prediction #16

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

Helene continued to become much better organized this evening. Estimates range from 100 to 120 kt at this point with a variance of pressure. The hurricane is now nearly symmetrical with a well-defined eye and very good outflow. The initial intensity is increased to 110 kt, which is a blend of the estimates.

Conditions remain very much favorable for intensification and should remain such at least for the next 48 hours, and perhaps throughout the forecast period. I now believe that Helene will at least make a run at Category 5 intensity as it tracks westward, south and southeast of Bermuda - although I peak the storm at this point at 135 kt. However, that is not set in stone - it could still easily move north or northwest instead. Shear might increase in the long range, but if not, it will be up and down with eyewall replacement cycles.



Current - 21.6/49.4 - 952mb - 125mph
12 hrs - 22.4/50.5 - 943mb - 140mph
24 hrs - 23.1/51.6 - 934mb - 150mph
36 hrs - 24.0/52.6 - 931mb - 150mph
48 hrs - 24.6/54.2 - 928mb - 155mph
60 hrs - 24.7/55.7 - 929mb - 150mph
72 hrs - 24.9/57.3 - 936mb - 140mph
96 hrs - 25.5/59.8 - 944mb - 125mph
120 hrs - 26.7/62.6 - 940mb - 135mph

[senorpepr]

Estimates are 100-105KT. What reliable sources are you seeing that say 120KT?

[SouthFloridawx]

Yeah where are you getting your data?

[Swimdude]

Estimates are 100-105KT. What reliable sources are you seeing that say 120KT?

I've actually noticed this in about 3 of this person's forecasts. The initial intensity is not always accurate...

[CrazyC83]

http://cimss.ssec.wisc.edu/tropic/adt/odt3.html had 118kt at one point (now 117), while I don't think it is THAT high, I used everything to come up with the 110 estimate.

[senorpepr]

http://cimss.ssec.wisc.edu/tropic/adt/odt3.html had 118kt at one point (now 117), while I don't think it is THAT high, I used everything to come up with the 110 estimate.

Why do you use that when it's known to over estimat when you have a few other reliable estimates showing 100-105KT?

[SouthFloridawx]

http://cimss.ssec.wisc.edu/tropic/adt/odt3.html had 118kt at one point (now 117), while I don't think it is THAT high, I used everything to come up with the 110 estimate.

Why do you use that when it's known to over estimat when you have a few other reliable estimates showing 100-105KT?

http://www.ssd.noaa.gov/PS/TROP/positions.html

I'm not sure where to get the A/F intensities estimates. But, if I were you before issuing current intensities... I would look at all the data and not base it off just one computer generated estimate. We're not trying to be critical just pointing out that you aren't using all the available data when making a decision.

[senorpepr]

I'm not sure where you can get AF estimates publically, but here is their latest:

TPNT KGWC 180041 COR
A. HURRICANE HELENE (EIGHT)
B. 17/2331Z (80)
C. 21.3N/6
D. 49.1W/4
E. TWO/GOES12
F. T5.5/5.5/D1.5/24HRS -17/2331Z-
G. IR/EIR

01A/ PBO 43NM (LRG) RND EYE/ANMTN. WMG EYE IS SURROUNDED
BY A 26NM WIDE LG RING GIVING AN EYE NBR OF 5.0. ADDED 0.5
FOR EYE ADJ FOR A CF/DT OF 5.5. FT IS BASED ON DT...MET
AGREES...BUT PT YIELDS A 5.0. COR FOR PCN IN LINE E.
COR SENT...18/0103Z.

AODT: T6.1 (LARGE CLEAR EYE)

LAURENTI



T5.5 yields 102KT.

[Matt-hurricanewatcher]

The eye has cleared out with half ring of red. Looks some what stronger then it did at the 11pm. So its perfectly in the room of reason that it has strengthen 5 to 10 knots. 105-110 knots at this time.

I like to see my cat4s with at least a red ring around the eye.

[CrazyC83]

Hurricane Helene Prediction #17

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

Helene continues to intensify over a warm, low-shear environment and now has a strong symmetrical structure. The eye is well-defined and quite clear, however, the fact that it is stronger on the E side suggests there is still room for organization. The intensity estimates range from 105 to 120 kt at this point. The initial intensity is increased to 115 kt, making Helene an extremely dangerous Category 4 hurricane.

The track is generally northwest after making an initial northerly turn. The ridge is building in behind Gordon and the trough is weakening, which should turn Helene to the west or even west-southwest for a while. Once clear of the ridge, the second trough should sweep Helene north then northeast. Bermuda may be at risk but the US East Coast shouldn't be unless that trough dissipates. The intensity forecast is kept at solid strengthening, modified by eyewall replacement cycles, throughout the forecast, due to the warm water and low shear - despite the fact that no guidance suggests such. Category 5 is definitely possible, most likely Tuesday night into Wednesday.



Current - 23.2/50.3 - 948mb - 135mph
12 hrs - 23.9/51.4 - 940mb - 145mph
24 hrs - 24.3/52.7 - 935mb - 150mph
36 hrs - 24.1/54.6 - 931mb - 155mph
48 hrs - 24.0/56.4 - 927mb - 155mph
60 hrs - 24.0/58.0 - 934mb - 145mph
72 hrs - 24.6/60.0 - 929mb - 150mph
96 hrs - 25.4/63.2 - 935mb - 140mph
120 hrs - 27.8/66.3 - 941mb - 135mph

[SouthFloridawx]

I just do not understand where you get your estimates from.

SSD indicates 18/1145 UTC 22.9N 49.7W T5.5/5.5 HELENE -- Atlantic Ocean

NHC estimates the winds as of 11AM @ 125MPH.

Your wind estimates are always higher than official intensities.

[Thunder44]

I just do not understand where you get your estimates from.

SSD indicates 18/1145 UTC 22.9N 49.7W T5.5/5.5 HELENE -- Atlantic Ocean

NHC estimates the winds as of 11AM @ 125MPH.

Your wind estimates are always higher than official intensities.

He may be using the ADT estimates from CIMSS, which are often too high.

[CrazyC83]

Hurricane Helene Prediction #18

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

Helene likely went through an eyewall replacement cycle this afternoon. The eye shrank in size and an aircraft flying into the storm found only Category 1 winds and a higher pressure. That being said, the storm still looks very impressive on satellite and the Dvorak numbers go as high as 125 kt. The initial intensity is set at 110 kt due to some questions on their basis.

With an eyewall cycle out of the way, Helene may already be re-strengthening. Even if she isn't, the opportunity for intensification is ample. Category 4 intensity should easily be reached, with a possible peak approaching Category 5 intensity. Additional eyewall replacement cycles should fluctuate the intensity. The track is still problematic - I still think the final northerly turn will be delayed as the trough comes in and sweeps Helene away from the US East Coast. It will come later than the NHC suggests, possibly threatening Bermuda.



Current - 24.1/51.3 - 952mb - 125mph
12 hrs - 24.3/52.8 - 943mb - 140mph
24 hrs - 24.5/54.3 - 936mb - 150mph
36 hrs - 24.9/55.9 - 934mb - 150mph
48 hrs - 24.8/57.4 - 929mb - 155mph
60 hrs - 24.4/59.0 - 938mb - 140mph
72 hrs - 24.6/61.3 - 943mb - 125mph
96 hrs - 26.2/64.5 - 937mb - 140mph
120 hrs - 28.9/67.3 - 940mb - 135mph

[wxmann_91]

Craig and all,

This is just constructive criticism. Please don't take this as an insult or bash or flame.

It is important for all forecasters to realize to be as unbiased as possible. See, the CIMSS AODT estimates are high. Most forecasters at the NHC discard those estimates and use the more reliable ones from TAFB/SAB/AFWA. Despite constructive comments from mets, it is still used in your forecasts.

That being said, the storm still looks very impressive on satellite and the Dvorak numbers go as high as 125 kt. The initial intensity is set at 110 kt due to some questions on their basis.

Am I saying go with the NHC and follow it? No, since all amateurs who are committed to make good forecasts should know to make forecasts before the NHC does. But don't be a sensationlist and foreacast doom and gloom... of course with the exception of when doom and gloom is looking very likely (for example, the projected upper air maps for Wilma were very indicative of the likelihood of a powerful hurricane, even when it was a disturbance).

Ioke was luck. Almost every other storm forecasted, has busted on the high side. I know you do not want to be a NHC forecaster, but it's just some advice. By no means am I telling you what to do and being your mommy; that's not my job.

You ask me - why am I not doing forecasts? Time constraints. Lame excuse, maybe, but trust me, I have done forecasts before last year - and I too was biased. They failed miserably.

I suggest verification for all amateurs who do forecasts. It does take some extra time, but if you are really committed to learning, it helps a lot.

NOTE that bias does not equal -removed-. (and I didn't even mention track!)

I'll step off my soapbox for now.

[dwg71]

Still think it will go west of Bermuda???

[storms in NC]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

This is why he puts this at the top of his post. He is just giving you what he thinks.
He didn't say this is going to happen only to let everyone know that this could happen not that is going to happen. I think he has do a good job at what he has done. If it is right or if it is wrong. But he has put time in to it. At the lease we can read and we can say why do you think this or that. That is what the board is for to let us learn what was right and wrong so next time we can do better