Thursday, August 26, 2004


This is not a drill, this is your worst fears (and mine) coming true. The lack of an El Nino this year in the East Pacific off Mexico and Peru has allowed the westerlies that usually move across the mid-latitudes to be "calmer." Notice how it has not been too hot this summer? That's partly due to the lack of influence of those classic southwesterly winds that pump warm air across the southern states into the Northeast.

Weak steering currents (westerlies) mean that hurricanes, if they form at just the right spot, can scoot right under the Bermuda High, and get shoved into the East Coast. That is the situation setting up for Frances. Please visit this Accuweather link for a graphic to explain what I just wrote:

I say 12 days because:
- Frances has formed in approximately the same location as Isabel
- The water in her path is very warm (85 F +)
- The blocking high to the north is going to prevent Frances from "going out to sea" as we like to hear storms do.
- If Frances travels at roughly the same forward speed as Isabel (about 17 mph), then you can expect it to be knocking on the East Coast front door by, say....Sunday, September 5.

The current and projected strength
- Cat 1 at 80 mph right now but gusting to 100 mph. That means strengthening.
- Expected to be a Cat 2 or 3 by the weekend, wind speed by Sunday... at least 120 mph.
- Will probably get to Cat 4 or 5 by Tuesday (sustained winds exceeding 140 mph)
- And she's got all that nice warm water out ahead of her... which should make you shudder.

A refresher for the Hurricane Classification Scale (The Saffir-Simpson Scale you hear on the news):

Category 1 - winds 75-90 mph - damage: minor - storm surge: 2-5 feet
Category 2 - winds 91-110 mph - damage: major - storm surge: 5-8 feet
Category 3 - winds 111-130 mph - damage: extensive - storm surge: 8-12 feet
Category 4 - winds 131-154 mph - damage: widespread - storm surge: 12-15 feet
Category 5 - winds 155+ mph - damage: catastrophic - storm surge: 15+ feet

How is this storm the same or different from Isabel?

- Frances has formed two weeks earlier than Isabel did (8/25/05 vs. 9/6/03) Waters off the Carolina/Chesapeake Bay were already cooling by 9/15 when Isabel arrived. If Frances arrives in early September, waters along heavily populated areas will be near the magic number of 80 F... the warmest they will be all year.

- Waters were also disturbed by a tropical system that moved along the coast the week before Isabel. This will not be the case this year.

- We have entered a dry spell on the East Coast.. for now. That looks to continue for at least a week, which is good news because whoever gets a direct hit does not have their soil saturated and tree roots weakened from heavy rain.

- The blocking high that shoved Isabel along a dead straight beeline for Virginia... has returned and is in generally the same position this year as it was last year. Remember the key is that if the Bermuda High edges a little bit EAST... storms go out to sea. If they edge a little bit WEST...well, you know.

- Frances formed in the same latitude/longitude block that Isabel did.

- Both Frances and Isabel ballooned out of nowhere, and went from a nothing to a hurricane in 24 hours. Isabel became Category 3 storm within 3 days, and Frances is forecasted to do the same.

- Both storms took an eerie little westward jog just as they increased strength. Had Isabel not had that minor course change, it would have probably missed the coast altogether. Frances has made that little shift already, and it forecasted to do it again this weekend. I remember getting that sinking feeling way back on September 10 when I saw a Category 3 storm way out in the Atlantic suddenly turn BACK towards the coast. Right then, I knew that we were in for it.

So what does this mean for the East Coast?

The total risk area (all potential landfall sites) : Miami to the Jersey Shore

The medium risk area (the most likely areas to see direct effects) :
South Carolina to Ocean City, MD

The high risk area (where I think it will make a direct hit): Nags Head, North Carolina.

Is there a risk this storm will charge up the Chesapeake Bay as a major (Category 3) storm, or even a Cat 2?

I am willing to go out on a limb and say that it appears Frances MAY NOT directly threaten the bay as Isabel could have. Remember if that storm had shifted it's track by just 50 miles to the east at landfall, damage to the Bay would have bordered on catastrophic. If the Bermuda High does not decide to drift eastward, and remains parked farther WEST than it is normally, this will influence the direction of Frances enough to prevent her from taking aim on the Bay. However, you know that once these storms get on the backside of that high, the tend to increase speed and start the infamous "curving" that we all seem to overlook until it is actually happening.

If Frances were to start curving too early, like the day before landfall, the Bay will be at risk.

The estimated day of landfall (at current forward speed):
SATURDAY, SEPTEMBER 4 around midnight OR:
SUNDAY, SEPTEMBER 5 around noon if there is any slowing in forward speed.

The estimated wind strength at landfall (based on past storm trends):
Frances will be a major hurricane just 24 hours prior to landfall, but if she moves into cooler waters, may lose some strength and come onshore as a strong Category 2 with winds around 110 mph. If the forward motion increases, and time over cooler water is limited, Frances will be the second landfalling major hurricane in one month's time.

What should I do?
No need for panic, the storm is very far away and no threat to land for at least 10 days. Believe me, if this thing even gets to Category 3, the news will be all over it like hair on a glorilla. If the storm appears to be threatening the I-95 corridor, I will post my very own specialized safety tips to keep you "ahead of the storm." So bookmark this page, tell your friends and be prepared.
The next update on Frances will be sometime Saturday or Sunday

No comments: