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Rainshadow

Dorian & Puerto Rico & Florida & The Carolinas

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23 hours ago, tombo82685 said:

Going to be interesting to see how Dorian responds once it gets out of upwelled waters. Euro has it deepening over 20mb. Also euro is still on the scrape or landfall around cape lookout or hse  area 

That >20mb last night is now 13mb tonight (same as UKMET run).  Still looks strange and it weakens 15mb in 6 hours and not because of landfall.

 

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2 minutes ago, Rainshadow said:

That >20mb last night is now 13mb tonight (same as UKMET run).  Still looks strange and it weakens 15mb in 6 hours and not because of landfall.

 

Yea bottoms it out at 935 I’d be shocked if we got more than a 10mph increase in winds. Probably like 5mph back up to 110. To large of a Storm as it takes more pressure drop to get wind response from Dorian. 

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13 minutes ago, tombo82685 said:

Yea bottoms it out at 935 I’d be shocked if we got more than a 10mph increase in winds. Probably like 5mph back up to 110. To large of a Storm as it takes more pressure drop to get wind response from Dorian. 

When you made the post yesterday I had to go shake the cobwebs in my head about the Coriolis effect, geostrophic wind and pressure gradient force. It rang a distant bell. To increase the geostrophic winds as a system (or exact same pressure gradient) moves north one has to increase the pressure gradient because the Coriolis contribution (sine of latitude) is more.  Now I have to take two aspirins.   

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6 minutes ago, Rainshadow said:

When you made the post yesterday I had to go shake the cobwebs in my head about the Coriolis effect, geostrophic wind and pressure gradient force. It rang a distant bell. To increase the geostrophic winds as a system (or exact same pressure gradient) moves north one has to increase the pressure gradient because the Coriolis contribution (sine of latitude) is more.  Now I have to take two aspirins.   

Yup, and a larger system is going to have a more spread out pressure gradient compared to a compact one. Thus you need more pressure drop to get a wind response. I’ll teach you Gigi, I’ll pur you under my wing and teach you how to fly 

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Interesting stuff.  Cranky had some good posts last night on what is allowing Dorian to slip ever further to the NNW. 

I can see conditions being a lot worse in Charleston than they expected.

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4 minutes ago, mshaffer526 said:

Interesting stuff.  Cranky had some good posts last night on what is allowing Dorian to slip ever further to the NNW. 

I can see conditions being a lot worse in Charleston than they expected.

I know we know that the hurricane is not a specific dot occupying one acre and the most destructive wind part is all about the eye wall which can be 20 to 40 miles from "the center".  So the hurricane could remain offshore, not make landfall, and still have the damaging wind impact the coast.  This does not take into consideration the storm surge, heavy rain, etc, which know no eyewall limitation.

89F for a high in Philly today?

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5 minutes ago, mshaffer526 said:

Interesting stuff.  Cranky had some good posts last night on what is allowing Dorian to slip ever further to the NNW. 

I can see conditions being a lot worse in Charleston than they expected.

WAR is also trending stronger again:

index.gif.e1fbce7337a55942f09591e829b529be.gif

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2 minutes ago, Rainshadow said:

I know we know that the hurricane is not a specific dot occupying one acre and the most destructive wind part is all about the eye wall which can be 20 to 40 miles from "the center".  So the hurricane could remain offshore, not make landfall, and still have the damaging wind impact the coast.  This does not take into consideration the storm surge, heavy rain, etc, which know no eyewall limitation.

89F for a high in Philly today?

Plus with the EWRC it had it made it easier for the coast to get into stronger winds as Dorian wind field spread out. 

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1 minute ago, Rainshadow said:

WAR is also trending stronger again:

index.gif.e1fbce7337a55942f09591e829b529be.gif

Shocker. 

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1 minute ago, tombo82685 said:

Shocker. 

Tugging west could also be from Dorian getting full enveloped into the trough and ridge in GOM moving west giving more room

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Have a friend in Hilton Head he’s at 17 feet elevation (luckily) but after discussion with him the past few days (and nudges west in storm’s track) he has decided to evacuate. I know it’s tough leaving your home behind but it’s not worth the stress the next 36 hours. I’m guessing they’ll have a prolonged period with 40-70 mph winds/gusts. Tidal/coastal flooding obviously will be a major issue. 

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1 hour ago, Parsley said:

Have a friend in Hilton Head he’s at 17 feet elevation (luckily) but after discussion with him the past few days (and nudges west in storm’s track) he has decided to evacuate. I know it’s tough leaving your home behind but it’s not worth the stress the next 36 hours. I’m guessing they’ll have a prolonged period with 40-70 mph winds/gusts. Tidal/coastal flooding obviously will be a major issue. 

This always boggled my mind. Maybe it’s because I’ve seen what these things can do, especially closer to sea level... but didn’t think it be that hard to leave. I get it, it’s your house and you’ve worked hard for it.Make your preparations, secure as best as possible and hope for the best. Not willing to gamble my life for property. Not much you can do when mother nature runs her course. Glad your friend did the smart thing. 

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So it’s not a PRE it just convergence that the euro and ukmet saturates column while gfs remain dry. 6z euro was drier west of 476. Still about an inch of rain in city but as a whole drier 

875769C6-1A12-4937-A3AE-9D1219E361C9.png

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19 minutes ago, irishbri74 said:

This always boggled my mind. Maybe it’s because I’ve seen what these things can do, especially closer to sea level... but didn’t think it be that hard to leave. I get it, it’s your house and you’ve worked hard for it.Make your preparations, secure as best as possible and hope for the best. Not willing to gamble my life for property. Not much you can do when mother nature runs her course. Glad your friend did the smart thing. 

I hear ya. You’ve seen it first hand. I told him I wasn’t going to make a decision for him (either way) but I think he made the smart choice. They had planned ahead and had a hotel booked inland since yesterday. Honestly until yesterday it looked like the primary threat was Myrtle Beach to Hatteras but things did trend west. It’s always tricky on the west side of the storm too with the sharp cutoff. Had he been anywhere further east I would have been more pushy with advice yesterday. 

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Heading to shore on friday PM weather permitting. Interestingly the highest AC tides are predicted for Saturday.

njatl.gif

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1 hour ago, tombo82685 said:

So it’s not a PRE it just convergence that the euro and ukmet saturates column while gfs remain dry. 6z euro was drier west of 476. Still about an inch of rain in city but as a whole drier 

875769C6-1A12-4937-A3AE-9D1219E361C9.png

If I may ask, what is PRE? I did a quick Google search but I couldn't seem to find anything.

We were planning to visit Fort McHenry on Saturday while we were in Baltimore, hopefully the rain stays out to sea. 

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4 minutes ago, mweav067 said:

If I may ask, what is PRE? I did a quick Google search but I couldn't seem to find anything.

We were planning to visit Fort McHenry on Saturday while we were in Baltimore, hopefully the rain stays out to sea. 

Predecessor rain event.  Proceeds tropical storms, not sure of the exact dynamics that cause it but itcan lead to an area of heavy rainfall well out ahead of tropical system. Probably has to be some sort of good convergence from a coastal front or something. We had one with hurricane Floyd

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1 minute ago, tombo82685 said:

Predecessor rain event.  Proceeds tropical storms, not sure of the exact dynamics that cause it but itcan lead to an area of heavy rainfall well out ahead of tropical system. Probably has to be some sort of good convergence from a coastal front or something. We had one with hurricane Floyd

How far inland would this happen? Not seeing much on models other than the Cape May area.

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47 minutes ago, Chubbs said:

Heading to shore on friday PM weather permitting. Interestingly the highest AC tides are predicted for Saturday.

 

Makes sense, consistent northeast winds stacking water up cycle after cycle

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3 minutes ago, cbelke said:

How far inland would this happen? Not seeing much on models other than the Cape May area.

It's not a PRE that the euro is showing, I was wrong on that yesterday.  It's just convergence

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1 hour ago, tombo82685 said:

So it’s not a PRE it just convergence that the euro and ukmet saturates column while gfs remain dry. 6z euro was drier west of 476. Still about an inch of rain in city but as a whole drier 

875769C6-1A12-4937-A3AE-9D1219E361C9.png

 Well some non-PRE rain given how September is returning to its recent dry self is still much appreciated.

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A tad slow on track forecast, but longitudinally pretty close given next forecast point. 
Dorian still verifying east of track forecast. Slower motion at 96 & 120 not hurting that thought.

10 am update: 29.7N 79.6W.

LOCATION...29.5N 79.6W. MAX SUSTAINED WINDS...105MPH. MOVEMENT...330 DEGREES AT 8 MPH. CENTRAL PRESSURE..964 MB
24H        29.2N 79.4W  95 KT 110 MPH
48H        29.3N 80.2W  110KT 125 MPH
72H        29.7N 80.2W  100KT 115 MPH
96H        30.5N 80.0W  100KT 115 MPH
120H       29.0N 81.5W   65 KT 75 MPH...INLAND

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2 hours ago, tombo82685 said:

Shocker. 

It goes thru the pendulum swing. First it starts too strong, then it weakens too much, then it starts coming back. 

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Along comes Dorian and the GFS's skill scores go....

2.JPG.c54afb756578982cf7ece4bd91cfc40f.JPG

Disclaimers: this is the entire northern hemisphere and the GFS's track scores are going to be pretty good with Dorian.  Also (I am assuming GS14 is previous version) its skill scores in the tropics 20S-20N are much better than its predecessor version, you know the one with the 895mb hurricanes. 

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1 hour ago, Rainshadow said:

Along comes Dorian and the GFS's skill scores go....

2.JPG.c54afb756578982cf7ece4bd91cfc40f.JPG

Disclaimers: this is the entire northern hemisphere and the GFS's track scores are going to be pretty good with Dorian.  Also (I am assuming GS14 is previous version) its skill scores in the tropics 20S-20N are much better than its predecessor version, you know the one with the 895mb hurricanes. 

Lol the ggem is beating the gfs?

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