Good Saturday Afternoon. I hope you are having a great Saturday. It is beautiful outside. Temps in the upper 70's with very low humidity. Lets get right to Irma.
As of 5:00pm:
...EYE OF IRMA BEGINNING TO MOVE SLOWLY AWAY FROM THE COAST OF CUBA WHILE WEATHER IS DETERIORATING IN SOUTH FLORIDA... ...MAJOR HURRICANE FORCE WINDS EXPECTED OVER THE FLORIDA KEYS AT DAYBREAK... SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...23.4N 80.5W ABOUT 50 MI...80 KM ENE OF VARADERO CUBA ABOUT 115 MI...190 KM SE OF KEY WEST FLORIDA MAXIMUM SUSTAINED WINDS...125 MPH...205 KM/H PRESENT MOVEMENT...WNW OR 295 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...933 MB...27.55 INCHES
Irma now looks like it will make landfall between The Florida Everglades and Tampa Bay Florida. After making landfall it will track North to a position just South of Macon Georgia as a Category 1 hurricane.. Here is the latest full track.
I don't want you to just look at this cone and think that we are out of the woods. While impacts will be less, we are still expecting gusts up to 60mph and sustained winds over 35mph. Those winds will peak on Monday Evening into the early nightime. It now appears though that the worst is behind us by the time we get up Tuesday. The rain will be tapering back to showers after only receiving 2-8 inches of rain across our viewing area. Here is the new graphic.
The next issue Ill address are the winds. Irma will move NW from Macon Georgia to a position just to the West of Atlanta by Tuesday Morning. Between 6pm Monday night and 3am Tuesday Morning high winds should cross the area. Winds will increase through the day on Monday as the pressure gradient steepens between a high pressure ridge to the North of us and Irma that will be to the SW of us. Lesson here. Wind ALWAYS blows from high pressure to low pressure. Picture the atmosphere as our local earths surface. Low pressure is the lowest/weakest point in the atmosphere so lets use The Linville Gorge for a reference. High pressure the highest and strongest pressure so lets use Table Rock for this. Now Earth's surface changes drastically from Table Rock to the bottom the Linville Gorge. The closer the base of the Gorge is to Table Rock the steeper the drop off (cliff) is going to be, right. Its the same principal in the atmosphere. The high pressure to our North and Irma's low will be fairly close together sandwiching us in between and that will steepen the pressure gradient. As Irma moves from Macon Georgia to a position just West of Atlanta Georgia she will start to unwind. Its like taking a ball of tightly wound rubber bands loose and letting them go. Pieces of energy from Irma will move NE away from the center. There is going to be a steep pressure gradient between the two air masses. Winds will become sustained 25-35mph over the Western Piedmont with gusts to 45mph. Over the foothills of Western NC we are expecting winds to be a little higher, sustained at 30-40mph with gusts to 55. In the mountains though the winds will be the highest. Up on the ridges winds will be 45-55mph with gusts up to 65mph. Locations above 5000 feet the winds could gust to 80+mph. Power companies expect power outages to begin when winds get above 40mph. So be ready for power losses on Monday Night through Tuesday Morning. Here is the graphic...
We also have to address the tornado thereat that looks to be increasing over our area. This threat will be Monday Afternoon through Tuesday Morning during the predawn hours. That means the possibility of seeing tornadoes during the night. This is where your family needs to have a plan. This will impact the area during the time where the winds will be the highest as well. So if you have to come out of your residence after a tornado then be aware that debris could still be flying around. We will watch this and address the situation as it becomes relevant on Monday.
Tuesday Morning things will start to wind down locally. We think we are done with any impactful weather other than using the chainsaws to cut the trees up that will have fallen by Noon. Now its not going to clear off rapidly.
All in all we are in a much better position than we were looking at just a couple of days ago. Don't panic but prepare. Stay weather aware Monday and Tuesday.