2026 Hurricane Forecast Cone: Inland Watches and Warnings

The U.S. National Hurricane Center’s (NHC) official 2026 cone adds inland watches and warnings. The cone shows uncertainty in the storm center’s track, not the size of the storm. Wind and flooding risks outside the cone must be checked in separate forecasts.

The figures and graphics here are based on NHC documents for the 2026 hurricane season.

What changed in the 2026 forecast cone

The official 2026 map shows inland tropical storm and hurricane watches and warnings. The previous official map showed U.S. coastal watches and warnings. The inland display was tested in 2024 and 2025. The change is described in NHC’s 2026 products and services notice.

The display covers the U.S. mainland, Hawaii, Puerto Rico, and the U.S. Virgin Islands. The entire 5-day cone uses the same shading. Diagonal stripes appear where a hurricane watch and a tropical storm warning overlap. The changes are also described in NOAA’s March 24, 2026 announcement.

The colors convey different information from track probabilities. Watch and warning areas show expected wind risks. Their boundaries do not have to match the cone’s boundary. The color definitions follow NHC’s graphics explanation.

What the forecast cone shows

The cone is the area where the center of a tropical cyclone may travel. It does not show the size of the whole storm or the area that may be affected. The center may also move outside the cone. NOAA’s Understand Forecast Information explains:

The cone does NOT represent the size of the storm in any way.

NOAA, Understand Forecast Information

The official cone is formed by enclosing circles placed at each forecast position. The radius of each circle is based on past track forecast errors. The errors used for 2026 are from 2021 through 2025. The circle for each forecast time encompasses about two-thirds of past errors.

These figures come from NHC’s 2026 cone definition. A radius is the distance measured from the forecast center position. It cannot be read as the probability of strong winds in a particular city. Nor does it assign the same probability to every point inside the cone.

Calculation example: the difference between radius and storm size

The 2026 Atlantic 48-hour forecast circle has a radius of 62 nautical miles. Its diameter is therefore 62 nautical miles × 2 = 124 nautical miles. This calculation gives only the diameter of a circle representing track error. It does not give the diameter of the actual storm or the radius of its strong winds.

Comparing the official and experimental cones

The experimental 2026 cone is provided separately from the official cone. It is a different change from adding inland watches and warnings to the official map. The experimental map changes the shape and criteria used to show track error. The method is described in NHC’s experimental cone explanation.

Error along the direction of travel measures how much faster or slower the storm moved than forecast. Side-to-side error measures how far it moved to either side of the forecast track. An ellipse represents the difference between these two directions. A difference in area between the maps should therefore not be interpreted as a change in storm size.

The experimental map uses a separate 90% inclusion level. This is not the probability of damage in a particular city. Nor does it guarantee that the storm’s entire track will always remain within the ellipses. NHC notes that the experimental product may be delayed during testing.

How watches and warnings differ

A watch means dangerous weather conditions are possible. A warning means those conditions are expected. Here, Watch is distinguished from Warning; this does not directly apply the names of South Korea’s weather alerts.

Tropical-storm-force sustained winds are 39 to 73 miles per hour. Hurricane-force sustained winds are at least 74 miles per hour. The time frame for a hurricane warning is based on when tropical-storm-force winds arrive. It is set to allow preparation before winds strengthen.

Pink and blue diagonal stripes do not indicate contradictory alerts. They mean tropical storm conditions are expected, but hurricane conditions are also possible. Being outside the cone is not a reason to ignore this marking. The definitions and time frames follow the U.S. National Weather Service’s explanation of watches and warnings.

Which sources show risks outside the cone

Wind and water forecasts should be checked separately for risks outside the cone. Strong winds can extend far from the storm center. Flooding from heavy rain can occur inland. Water damage can continue even after a hurricane is downgraded.

Wind probability maps show the chance that winds will reach a specified speed during a set period. They measure something different from the cone’s 67%. The functions of these products are described in NHC’s graphics explanation.

The earliest reasonable arrival time is a more conservative measure than the most likely arrival time. NHC says the chance of winds beginning before that time is 10% or less. That time is therefore not an absolute deadline for safety. The definition is given in NHC’s guidance on wind arrival times.

Local weather office information should also be read to understand impacts in a particular area. A Hurricane Local Statement summarizes expected impacts. It covers flooding and tornadoes, among other risks, as well as wind. Its role is described in the U.S. National Weather Service’s explanation of local forecast products.

Situations and common misunderstandings

Whether an area is inside the cone does not, by itself, determine its risk. The cone and watches or warnings answer different questions. The table below applies the definitions explained above to different situations.

Reading the area outside the cone as a safe zone is a common misunderstanding. A narrower cone does not necessarily mean less damage. Storm size and rainfall risk must be assessed using separate information. NOAA’s guidance on interpreting forecasts emphasizes these distinctions.

Information to preserve when sharing a map

When sharing a map or saving its data, keep its issuance details with it. The image’s appearance alone may not establish whether it shows the same forecast. The items below are criteria for sharing a map drawn from NHC’s product descriptions.

A wind arrival map uses one time zone based on the storm’s location. The map may retain that time zone even if the forecast track crosses into another one. The displayed time should therefore not automatically be treated as local time at the arrival location. This approach is described in NHC’s arrival time product explanation.

More than one watch or warning status can apply to the same area. Saving only one in a dataset would therefore lose the meaning of the diagonal stripes. NHC’s TCV distinguishes watch and warning types by code. The code structure is described in the Tropical Cyclone Watch/Warning explanation.

On rare occasions, a preliminary cone without inland watches and warnings may be posted first. In that case, a map showing only coastal watches and warnings is provided temporarily. The absence of inland markings alone should not be taken to mean that watches or warnings have been lifted. This exception is noted in NHC’s 2026 changes notice.

Why it still matters in October

The Atlantic hurricane season officially runs through November 30. A seasonal outlook predicts activity levels for the season as a whole. It does not forecast whether a storm will make landfall in a particular area. This distinction is stated in NOAA’s update to its 2026 seasonal outlook.

The U.S. National Weather Service’s Mobile/Pensacola September climate summary also stresses the need to prepare for October. The document is dated October 1, 2026. Its point is that a period of low activity does not, by itself, establish that the risk has fallen for the rest of the season. The original is available in September 2026 Climate Summaries.

Assess actual local risks using the latest NHC forecast and local weather office watches and warnings. Check instructions from local authorities when deciding whether to evacuate. The activity level in a seasonal outlook cannot be read as a personal probability of safety.

Frequently asked questions

Were inland watches and warnings introduced in 2026?

Inland watches and warnings themselves were not introduced in 2026. The 2026 change is their display on the official cone map. Existing inland watches and warnings were available from local weather offices and in TCV data, among other sources.

Does being inside the cone mean the hurricane will pass directly overhead?

Being inside the cone does not mean the center will necessarily pass over a location. The cone represents uncertainty in the center’s track. Check wind probability maps for the chance of strong winds at a specific location.

Has the experimental cone replaced the official cone?

The experimental cone does not replace the official cone in 2026. Both products are provided. The experimental product’s 90% criterion should not be read as the criterion for the official product.

Can flooding occur outside the cone?

Flooding can occur outside the cone. The areas affected by heavy rain and storm surge differ from the center’s track. Check rainfall forecasts and local flood warnings separately.

Does the 36-hour period for a hurricane warning mean time until landfall?

The 36-hour period for a hurricane warning does not refer to when the center will make landfall. It is based on the expected arrival of tropical-storm-force winds. The period is set to allow preparation before strong winds begin.

Does this explanation stop applying after November 30?

November 30 is the official end of the Atlantic hurricane season. It is not the day the explanations of the cone and watches and warnings cease to apply. Circle radii change from year to year, however, and should be checked in the documents for the relevant year. (Verified 2026 circle radii by forecast time, Atlantic / eastern and central North Pacific: 12 hours 25/25 nautical miles, 24 hours 39/37 nautical miles, 36 hours 49/48 nautical miles, 48 hours 62/56 nautical miles, 60 hours 77/66 nautical miles, 72 hours 95/78 nautical miles · source nhc.noaa.gov · checked 2026-10-20)