Hurricane Watch In Effect
As of the 5am advisory, Hurricane Matthew is strengthening as it moves through the Bahamas and approaches Florida. Pressure is down to 944 millibars and appears to be continuing to drop based on observations from reconnaissance aircraft flying through the storm. This is a very, very bad scenario for the east coast of Florida.
For our part, a Hurricane Watch is now up for Berkeley and Charleston counties, while a Tropical Storm Watch is in effect for Dorchester County where wind effects should be less pronounced. A Flash Flood Watch has also been issued for the Tri-County area through the duration of the event. I think water is going to be a very big problem; more on that in a minute.
The Hurricane Watch is your signal that time is starting to tick away for preparations and evacuations. A Hurricane Watch means that hurricane conditions — defined as sustained winds 74 mph or greater — will be possible within the watch area within 48 hours.
Should I evacuate?
If you’re in an evacuation zone, haven’t left yet, and are wondering whether you should go, err on the side of caution and go. I suspect it will take a few days for life to return to normal, especially if the worst case pans out. Long-duration power outages will certainly be a factor in some places, and inundation from storm surge as well as extremely heavy rainfall will lead to flooding problems. For some places particularly near the coast, the increased surge and heavy rainfall may make things worse than last October.
Put another way, if you were helped by rescuers out of your home last year, incurred significant flood damage, or were otherwise very concerned for your safety during last year’s storms, leave.
Flood threat
Winds always grab the headlines with a hurricane, but water is what does the most damage. A Flash Flood Watch goes into effect Friday morning as very high rainfall totals exceeding 10" in many locations will almost certainly cause flooding. The heavy rainfall combined with storm surge around 4+ feet will cause significant flooding in low-lying areas (looking at you, downtown Charleston).
Take the flood threat seriously. We may be living with this for several days especially near rivers. I reiterate that if you had significant problems with flooding last October, you should strongly consider evacuating today.
Timeline
As of 5am, here’s a rough idea of what the timeline looks like. This is highly subject to change based on track adjustments.
- Today: Cloudy and breezy along the coast (not Matthew-related, yet). Highs mid to upper 70s. This is the last good weather we will probably have until Sunday evening — take advantage of it and finish your preparations today.
- Tonight: Periodic showers. Still breezy. Lows around 70.
- Friday: Heavy rain begins. Weather to deteriorate throughout the day; flash flooding threat increases. Winds will be breezy out of the east and northeast. High temperature 78.
- Friday Night: Things start to go downhill quickly. Sustained winds will increase well into tropical storm force (39+ MPH) with higher gusts to hurricane force. Heavy rainfall and flash flooding concerns will increase. Tidal flooding will become a significant factor. If you haven’t left by Friday night, stay put.
- Saturday into Saturday night: Worst weather of the period. Saturday brings our highest storm surge and threat for hurricane-force sustained winds particularly near the coast. Extreme rainfall expected Saturday with a risk of freshwater flooding well inland. Stay indoors.
- Sunday: Rain and wind will begin to slacken in the morning. Rain is currently forecast to end by afternoon, and clouds should begin to scour out. Breezy north winds will continue. High 76.
What to Do
- Take a breath. This is stressful for everyone involved. If we all remember to take a few minutes to reset ourselves and not worry about the things outside of our control, this is going to go extremely well for us.
- Finish your preparations today. If you need to evacuate, today’s the best opportunity to do so smoothly. Lane reversal on I-26 will remain in effect until at least Friday morning, and by all accounts yesterday it was extremely effective in shuttling a lot of traffic out. See SCDOT’s website for travel times along key evacuation routes.
- Continue to monitor forecast updates and information from local emergency management officials, particularly if you decide to stay. Things may change on a dime, and not in a good way. Stay alert to your surroundings and be prepared to take action to save your life. Remember, if you stay, first responders may not be able to make it to you if you call 911 during the height of the storm. If this prospect at all worries you, leave.
More updates today as needed on Twitter. Stay safe, everyone.
