Tropical Storm #Hilary - Are you familiar with tropical cyclone products?
A thread:
16Aug2023
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Updates: Who/When:
All US Tropical Storm / Hurricane updates come from US National Hurricane Center(NHC). Apps/news use their info. Updates every 6hrs at 2 & 8a/pPDT. If Tropical Storm or Hurricane Watch/Warning issued for land then they update every 3hrs. https://hurricanes.gov
NHC works with local partners to disseminate storm information. This includes different levels of gov and National Weather Service(NWS). Your local NWS office can give you specific storm threats for your location. Visit: https://weather.gov
enter city/zip in top left box.
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Weather Apps?
In more dynamic situations seek an actual human. Apps are great for helping push Warnings out to you and general day to day, but for complex tropical system impacts you're better off with a pro.
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Cone map?
Probably the most recognized tropical cyclone product. Reminder the cone size is not the storm size/strength, it's just the average error that far out in time where center point may be. Impacts will be felt well outside & ahead of this 'cone'
#Hilary 16Aug2023 8pPDT
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Why is top 'S' dot white for Monday while others darker?
The dark S (Tropical Storm), dark H (Hurricane), dark M (Major Hurricane (Cat3+)) are tropical system intensities.
White dot means not expected to be 'tropical' anymore, just a regular old Low. Impacts same/similar though.
The arrival time of winds map can help tell you when winds of 39mph or higher starting time may occur due to a tropical system. For the US East coast, that's enough wind speed to start to cause downed trees, scattered power outages.
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Wind speed probability maps can help show percent chance of seeing 39mph or higher winds due to a tropical system. Keep in mind this is just winds from a tropical system...it won't show winds from other sources that may occur here. Check with local NWS for additional information.
What's Hurricane Watch/Warning, when issued?
They are a time based issued alert for Hurricane winds of 74mph or greater.
Hurricane Watch: Winds possible within 48 hours or less.
Hurricane Warning: Winds expected within 36 hours or less.
#Hilary
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Storm Surge Watch/Warning, when issued?
They are a time based issued alert for Storm Surge (Ocean rises, like it's own tide level) of 3ft or more
SS Watch: Surge possible within 48 hours or less.
SS Warning: Surge expected within 36 hours or less.
(does not include wave heights)
Wait...why is Warning bad in weather but good when shiny blue lights are behind you while driving??
Yes, it's the opposite...
In Weather 'Watch' means ingredients in place to happen, but 'Warning' means it is occurring or imminent and to take action.
12/x #Hilary
What are Key Messages?
There's a lot of storm information text, graphics and data. Key Messages graphics provide a brief summary of important information about a specific tropical system. This may include safety and storm hazard information, future track guidance, confidence, etc
@WeatherSources Thanks for doing these!
What's Tropical Storm Watch/Warning, when issued?
They are a time based issued alert for Tropical Storm winds of 39mph or greater.
TS Watch: Winds possible within 48 hours or less.
TS Warning: Winds expected within 36 hours or less.
#Hilary
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