Soliciting Comments on
Future Local Tropical Cyclone Watch/Warning
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The NWS wants your input on the way we deliver local tropical storm and hurricane information!
To speed up the issuance of potentially life-saving tropical storm and hurricane watches and warnings, the NWS is proposing to streamline the Local Tropical Cyclone Watch/Warning (TCV) text product to focus only tropical wind (tropical storm and hurricane) hazards.
Examples of the proposed changes can be found in the table below, and you can submit your feedback here or by sending an email to Tropical.Program@noaa.gov, but we suggest that you check out the background and proposal information for more details first.
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Proposal
The NWS is proposing to:
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Streamline the Local Tropical Cyclone Watch/Warning (TCV) text product to focus only tropical wind (tropical storm and hurricane) hazards so that potentially life-saving watches/warnings can be sent out at the same time as the NHC/CPHC advisory.
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As recommended by social scientists, include explicit probabilistic wind forecast information to account for the uncertainty in the forecast, giving the user a heads up on the potential “worst case scenario” for wind in their area
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Change the text format of the Local TCV product to align with the “What, Where, When” format seen in most other NWS products
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Move storm surge watches/warnings to the Coastal Hazard Message products so that all storm surge and coastal flooding hazards can be provided in one product and more geographical specificity can be provided in their depiction by providing supplemental polygon-based hazard areas. See this web page for more details.
The current Local TCV product includes information on flooding rain and tornado conditions. The inclusion of this information, all of which is routinely available in NWS products regardless of whether they are associated with a tropical cyclone or not, slows down the issuance of potentially life-saving tropical storm and hurricane watches and warnings. Flooding rain and tornadoes are not unique to tropical cyclone events. Information on these hazards, including watch/warning information which is not provided in the Local TCV, is always available through the routine suite of rainfall, flooding, and severe weather NWS products and services.
The Hurricane Local Statement (HLS) will continue to be a “one stop shop” overview of hazard information during a tropical cyclone event. The proposed future Local TCV would include a link to the local WFO Tropical Web Page (example) where the HLS and hazard-specific information for the local area can be found.
Background
The current Local Tropical Cyclone Watch/Warning (TCV) product is the vehicle for the issuance of tropical storm, hurricane, and storm surge watches and/warnings including Valid Time Event Code (VTEC). However, the Local TCV also provides information on flooding rain and tornado hazards. The product is dependent on over 20 distinct sources of wind, storm surge, flooding rain, and hazard information. If any of these pieces of information is not present, the issuance of tropical storm, hurricane, or storm surge watches/warnings is at risk of being delayed. Because the Local TCV includes so much information, it is very long and has exceeded the dissemination limit for NWS systems on more than one occasion, delaying the issuance of watches and warnings.
Here is an example of just one NWS zone-based segment of the current Local TCV text product:
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FLZ165-272330-
/O.CON.KTBW.HU.W.1009.000000T0000Z-000000T0000Z/
/O.CON.KTBW.SS.W.1009.000000T0000Z-000000T0000Z/
Coastal Lee-
1116 AM EDT Tue Sep 27 2022
...HURRICANE WARNING REMAINS IN EFFECT...
...STORM SURGE WARNING REMAINS IN EFFECT...
* LOCATIONS AFFECTED
- Cape Coral
- Captiva
- Sanibel
* WIND
- LATEST LOCAL FORECAST: Equivalent Cat 1 Hurricane force wind
- Peak Wind Forecast: 55-75 mph with gusts to 90 mph
- Window for Tropical Storm force winds: early this evening
until Thursday evening
- THREAT TO LIFE AND PROPERTY THAT INCLUDES TYPICAL FORECAST
UNCERTAINTY IN TRACK, SIZE AND INTENSITY: Potential for wind
greater than 110 mph
- The wind threat has remained nearly steady from the
previous assessment.
- PLAN: Plan for extreme wind of equivalent CAT 3 hurricane
force or higher.
- PREPARE: Remaining efforts to protect life and property
should be urgently completed. Prepare for catastrophic wind
damage.
- ACT: Move to safe shelter before the wind becomes hazardous.
- POTENTIAL IMPACTS: Devastating to Catastrophic
- Structural damage to sturdy buildings, some with complete
roof and wall failures. Complete destruction of mobile
homes. Damage greatly accentuated by large airborne
projectiles. Locations may be uninhabitable for weeks or
months.
- Numerous large trees snapped or uprooted along with fences
and roadway signs blown over.
- Many roads impassable from large debris, and more within
urban or heavily wooded places. Many bridges, causeways,
and access routes impassable.
- Widespread power and communications outages.
* STORM SURGE
- LATEST LOCAL FORECAST: Life-threatening and historic storm
surge possible
- Peak Storm Surge Inundation: The potential for 8-12 feet
above ground somewhere within surge prone areas
- Window of concern: Begins this evening
- THREAT TO LIFE AND PROPERTY THAT INCLUDES TYPICAL FORECAST
UNCERTAINTY IN TRACK, SIZE AND INTENSITY: Potential for storm
surge flooding greater than 9 feet above ground
- The storm surge threat has increased from the previous
assessment.
- PLAN: Plan for extreme life-threatening storm surge
flooding greater than 9 feet above ground.
- PREPARE: Evacuation efforts should soon be brought to
completion before driving conditions become unsafe.
- ACT: Leave immediately if evacuation orders are given for
your area to avoid being cut off from emergency services or
needlessly risk lives.
- POTENTIAL IMPACTS: Devastating to Catastrophic
- 3 FT surge above high tide floods beaches in barrier
islands.
- 4 FT surge above high tide floods Matlacha and cuts off
causeway to Pine Island.
- 4 FT surge above high tide cuts off the causeway to Sanibel.
- 4 FT surge above high tide floods much of Bokeelia and ST
James City.
- 5 FT surge above high tide begins to submerge Cape Coral
and Fort Myers west of U.S. 41 and south of Daniels Parkway.
* FLOODING RAIN
- LATEST LOCAL FORECAST: Flood Watch is in effect
- Peak Rainfall Amounts: Additional 4-8 inches, with locally
higher amounts
- THREAT TO LIFE AND PROPERTY THAT INCLUDES TYPICAL FORECAST
UNCERTAINTY IN TRACK, SIZE AND INTENSITY: Potential for major
flooding rain
- The flooding rain threat has remained nearly steady from
the previous assessment.
- PLAN: Emergency plans should include the potential for
major flooding from heavy rain. Evacuations and rescues are
likely.
- PREPARE: Strongly consider protective actions, especially
if you are in an area vulnerable to flooding.
- ACT: Heed any flood watches and warnings. Failure to take
action will likely result in serious injury or loss of life.
- POTENTIAL IMPACTS: Extensive
- Major rainfall flooding may prompt many evacuations and
rescues.
- Rivers and tributaries may rapidly overflow their banks in
multiple places. Small streams, creeks, canals, and ditches
may become dangerous rivers. Flood control systems and
barriers may become stressed.
- Flood waters can enter many structures within multiple
communities, some structures becoming uninhabitable or
washed away. Many places where flood waters may cover
escape routes. Streets and parking lots become rivers of
moving water with underpasses submerged. Driving conditions
become dangerous. Many road and bridge closures with some
weakened or washed out.
* TORNADO
- LATEST LOCAL FORECAST:
- Situation is favorable for tornadoes
- THREAT TO LIFE AND PROPERTY THAT INCLUDES TYPICAL FORECAST
UNCERTAINTY IN TRACK, SIZE AND INTENSITY: Potential for several
tornadoes
- The tornado threat has increased from the previous
assessment.
- PLAN: Emergency plans should include the potential for
several tornadoes with a few possibly intense having larger
damage paths.
- PREPARE: Those living in manufactured homes or on boats are
urged to relocate to safe shelter before hazardous weather
arrives.
- ACT: Listen for tornado watches and warnings. If a tornado
warning is issued, be ready to shelter quickly.
- POTENTIAL IMPACTS: Significant
- The occurrence of scattered tornadoes can hinder the
execution of emergency plans during tropical events.
- Several places may experience tornado damage with a few
spots of considerable damage, power loss, and
communications failures.
- Locations could realize roofs torn off frame houses, mobile
homes demolished, boxcars overturned, large trees snapped
or uprooted, vehicles tumbled, and boats tossed about.
Dangerous projectiles can add to the toll.
* FOR MORE INFORMATION:
- https://www.weather.gov/tbw
$$
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In addition, the forecast information in the current Local TCV includes a deterministic forecast and an implicit forecast of what to prepare for in the “ THREAT TO LIFE AND PROPERTY THAT INCLUDES TYPICAL FORECAST UNCERTAINTY IN TRACK, SIZE AND INTENSITY:” section. Recent social science studies have shown that it is important to explicitly state probabilistic information to better allow the user to evaluate their level of risk.
Finally, the format of the Local TCV is unlike any other NWS product. Adopting a “What, Where, When” format would align the Local TCV with other NWS products and allow routine users to more easily find or parse the information they are looking for.
Feedback
Please provide your feedback or this proposal through this website. Alternatively, you can email your feedback or direct your questions to tropical.program@noaa.gov.
