Frequently Asked Questions


Who is eligible to have HURREVAC? How do I get it?

HURREVAC is funded by the federal government and is available free-of-charge to eligible users. According to federal guidelines, program access is restricted to the government emergency management community.

Visit the registration page on and fill out the form to apply for an account. Once registered, you will receive an email with instructions on how to log in for the first time.

Can I have program access if I’m not an emergency manager?

HURREVAC access is not provided to private entities. If you work with critical infrastructure in a role that supports emergency management agencies, please have a point of contact from the emergency management agency submit a request for access.

I think I may be registered under an old e-mail address and I’m concerned that future HURREVAC announcements will not reach me. What should I do?

Simply reregister as if you’re a new user. If the registration page alerts you that the email address you want to use is already associated with a user account, contact us at and we will help you update the information.

May I share my HURREVAC access with other emergency management colleagues?

In general, it’s recommended that each person maintain their own user account in HURREVAC. That way, any program preferences that you store cannot be overwritten by other users.

I forgot my HURREVAC login, or I would like to change my password. How do I do that?

Visit and click on the blue “Launch HURREVAC Application” button to get to the login screen. Then, click “Forgot Password.” From there, you can enter your username or email address to be sent instructions on how to create a new password. Contact for assistance if this recovery email does not appear in your inbox within several minutes, or if you encounter other difficulties with regaining account access.

Can I use HURREVAC in international areas?

HURREVAC plots all active storms worldwide, but some map layers created by the NHC and CPHC are only available for the United States and US territories. The National Hurricane Program has supported international partners in limited cases.



Are there any special hardware or software requirements for computers to run HURREVAC?

HURREVAC is a web browser-based program and can be used on most computers or tablets that have a modern web browser such as Chrome, Firefox, or Edge. Note: HURREVAC does not work in Internet Explorer 11. HURREVAC has not yet been optimized for small screens such as smartphones, however you may still find some utility on those devices.

How do I get the most recent version of HURREVAC?

HURREVAC is web-based, so you automatically get the latest version whenever you log in. There is no need to download any updates or releases like in the past desktop version.

Can I see HURREVAC on my smartphone? is there an iOS version?

HURREVAC can be accessed from web browsers on mobile devices, however the interface is not optimized for smaller screen sizes. HURREVAC is not available as a standalone app, so there are no versions specific to iOS or Android.

Can I use HURREVAC on a tablet? Is it optimized for touch?

Yes, you can use tablets or other touch devices to navigate HURREVAC, but we recommend using a mouse for the best experience.

How do I get HURREVAC during power or internet outages?

It is critical that agencies have a contingency plan in place for accessing the most up-to-date information. In the event of power or internet outages, it is recommended that partners contact support agencies for assistance in getting the latest information. You may also use HURREVAC on your smartphone and/or tablet if there is mobile data coverage.

During a real storm, can the HURREVAC server handle thousands of users simultaneously?

HURREVAC is cloud-hosted and configured to scale up server resources as needed. Several thousand users were simultaneously logged in and using the system during the large storm events of the 2020, 2021, and 2022 Atlantic hurricane seasons, and there were no limitations to program performance or additional users joining.

When I log in, the interface looks faded-out and I can’t interact with anything. What’s the matter?

You didn’t make any mistakes, but you’ll need our help to keep using the program. Reach out to for assistance, we can make a quick adjustment to your user profile to restore functionality.



I’m new to HURREVAC. Where do I learn the basics of the program?

A good place to start is The Learning Resources page has training videos from the five-day webinar series and a quick reference guide in PDF format. Once logged into HURREVAC, you can reference the comprehensive built-in User Guide. Just click the question mark icon in the lower right section of the workspace. You can also click “Training” in the toolbox (lower left corner), which contains self-guided training modules.

Who can help with HURREVAC and its products when we are facing a tropical threat?

For questions about HURREVAC accounts and functionality, users have year-round access to technical support from Sea Island Software, the contractor who develops, operates and maintains the system. The toll-free support line is (888) 840-4089. Routine requests emailed to are answered within one business day. During active storms with watches and/or warnings in effect, time-critical user needs are addressed immediately even outside of business hours.

For questions regarding hurricane forecast products, the Hurricane Liaison Team (HLT) is available to help give additional information on confidence, contingencies and forecast and evacuation timing. The HLT is also available to provide briefings to emergency managers after forecast products are released. Contact your FEMA regional program manager to learn more.

Will there be a refresher course this year to review the new HURREVAC features?

Yes. The 2023 webinar series will be held during the week of June 12 – click here for registration information. Visit the Learning Resources page at to review previous webinar recordings and handouts.

A quick rundown of what’s new in HURREVAC for 2023 is posted under Announcements on, and that’s where we’ll post information about other changes currently under development.

To request specialized training for your group or agency, contact your state’s hurricane planner or the NHP representative for your FEMA region or USACE district. Email addresses for these individuals are provided within HURREVAC under the “Library” heading of the “Resources” tab.



How do I get current storm information into HURREVAC?

The program has built-in polling to monitor the servers at and import new storm data when available. HURREVAC also intelligently retrieves older data (such as archived storm tracks and previous text advisories) whenever these products are selected for display.

Do I have to refresh HURREVAC to see the latest advisory? How long does it take to update

When the NHC or CPHC comes out with new advisories, HURREVAC usually updates within a minute or two of the advisory products becoming available on NOAA’s sites and servers. Certain storm surge-related map layers require additional time to process and issue. Potential Storm Surge Flooding is typically available 45 minutes to one hour after the advisory time.

If you are having latency issues or an unreliable internet connection, we recommend reloading the site to make sure you see the latest data. When the HURREVAC site reloads, you will have to select the storm and map layers again.

Why did I get a notification to check my internet connection?

When you get a “check internet connection” notification in the upper right part of the HURREVAC tracking map, it indicates there was a break in the browser’s constant connection to the HURREVAC server. (This replaces the flashing yellow triangle icon that was used prior to June 2023).

Sometimes this is due to your computer going into sleep mode, or a local firewall timing out the connection. For some users, this may happen more often due to their VPN connection. A temporary loss of connection can impede the automatic updates of new storms or new advisories of active storms, but the program should otherwise continue to operate when you begin interacting with it again.

When disconnects happen, you can reload the website to get back up to date. Or, you can uncheck and recheck the storm (in the Storms tab) if you expect that an updated advisory is available and should be displayed. This causes HURREVAC to reconnect to the server to retrieve that data specifically. When the internet connection is constant, HURREVAC’s map automatically refreshes when new advisories are available.

This notification could also appear when there is sustained loss of connection beyond HURREVAC’s control due to your device going offline.

Can the products in HURREVAC be changed to reflect a time zone other than where my computer is?

Yes, time display settings can be changed. To do so, click “User Preferences” (gears icon) in the utilities bar (along the right side of the workspace) to open the User Preferences window. Then, click the “Map Settings” tab. There is a dropdown menu next to “Time Zone.”

The default choice is “Match Device Setting,” but a user can select a custom number of hours ahead or behind of UTC (Zulu). Remember to adjust this setting when your location of interest observes daylight saving time.

Which computer model is used for the forecast track?

The tracks shown in HURREVAC are always an official forecast issued by the National Hurricane Center, Central Pacific Hurricane Center, or Joint Typhoon Warning Center.

The experts at the forecast agencies consider many factors – including the performance of the various global and regional computer models – before they produce forecasts. The official NHC, CPHC or JTWC products are therefore recommended for emergency management decisions.

On average, NHC track errors are lower than any individual model. NHC forecast tracks are also more consistent compared to model tracks, which can veer back and forth throughout the day.
Users interested in learning about the sources of track uncertainty are encouraged to read the Forecast Discussion, which can be found in the “Text Advisories” section of the HURREVAC toolbox.

Can I use HURREVAC to see the ‘spaghetti models’ that show all the places a hurricane might track? Will forecast models be added to HURREVAC?

HURREVAC is not designed for viewing raw computer model output. There are no plans to add forecast model data to HURREVAC. The official NHC, CPHC or JTWC products are recommended for emergency management decisions.

Is there a way to overlay map services or local data?

Custom “points of interest” can be manually added to your HURREVAC workspace or imported from a properly formatted Excel spreadsheet. Refer to the User Guide for more details.

You cannot upload or import map files (shapefiles, KML/MKZ, rasters, lines or polygons) into HURREVAC. To perform more sophisticated analysis, the best method is to download storm advisory or storm surge information from HURREVAC and load those layers into GIS software.

Which HURREVAC layers can I export to use in GIS programs?

When a storm is selected, the following products can be downloaded in GeoJSON format by clicking “GIS Export” in the utilities bar on the right side of the workspace. (To use as a shapefile or other format, you’ll need to use a third-party file converter like Note that the compressed (zip) file only downloads layers for the advisory that is actively showing on the map.

  • Advisory points (past and current points)
  • Past track (line)
  • Forecast track (line and points)
  • Potential track area /error cone (polygon)
  • Wind watches and warnings (lines)
  • Location-based wind probabilities (points)
  • Forecast wind fields / wind ring (polygons)
  • Past wind swath (polygon)

There are two ways to download storm surge hazard maps in GeoTIFF format. Click “Export Data” when layers are selected in the “Storm Surge (SLOSH) Explorer” panel, or look in the direct download folders under the “Resources” tab. Note that these may be very large files.

  • MOMs (US National, Hawaiian Islands, Hispaniola, Puerto Rico, US Virgin Islands)
  • MEOWs (by SLOSH basin)
  • SLOSH Hindcasts (for select Atlantic storms since 2020)

Is there an API?

HURREVAC is not built to support external applications’ use of its API at this time.

What’s the difference between an exercise storm and a simulated storm in HURREVAC?

The “Exercise Storms” folder in HURREVAC contains storms that are created for use in live exercises. These storms are managed by HURREVAC’s administrators, so it is not possible to add, edit or remove them from your workspace.

HURREVAC’s Storm Simulator lets users create and share their own custom hurricane scenarios to support planning, training, and exercises. (Refer to the User Guide for step-by-step instructions.) These are saved to the “Simulated Storms” folder. This section of the Storms tab is empty until you have made a simulated storm or imported one from another user.

Both folders are listed in the “Storms” tab, beneath active storms and archived storms dating back to 2005.