Important Disclaimers: The system producing these charts uses numerical model data from NOAA servers, but this site and these charts are not associated with nor endorsed by NOAA or the National Weather Service. These charts should not be used as official forecasts, but rather as model guidance products. The LCR scale is experimental and the system producing these charts is in a beta stage of development.
Note: You may need to refresh the page to see the newest charts. Visit the LCR main page for complete documentation.
Please see: Explanation of Parameters | Frequently Asked Questions
Time and date of last chart set generation: 01z 01/21/2025
Short-term forecast charts (updated hourly)
These charts are generated hourly from the HRRR model and show maximum LCR and BFP+ from now through the next 6 hours. Click each chart to view its full size.
6-Hour LCR (Loss-of-Control Risk)
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6-Hour BFP+
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24-hour forecast charts (updated 4 times daily)
These charts are generated four times a day from the 00z, 06z, 12z and 18z runs of HRRR model and show maximum LCR and BFP+ over the following 24-hour period. Click each chart to view its full size.
The most recent 24-hour chart was generated at 00z 01/21/2025.
24-Hour LCR (Loss-of-Control Risk)
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24-Hour BFP+
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Recently-generated chart archives
Short-term forecast archives (last 24 hours):
24-hour forecast archives (last 5 days):
Explanation of Parameters
LCR (Loss-of-Control Risk): The risk of a motor vehicle losing control due to reduced road surface friction from winter precipitation. Based on 1-hour precipitation amounts (QPF), precipitation type, surface temperature, surface dewpoint, surface relative humidity and surface wind gusts. LCR charts show the maximum values of LCR expected during the time period represented on the chart. See the main LCR page for detailed synopsis of LCR calculation.
BFP+: BFP Plus charts plot all precipitation (liquid-equivalent QPF) in the context of surface temperature. Different color scales are used for each temperature range:
- CIP (Precipitation at/below Critical Icing Temperature), Highest Risk: The amount of precipitation (QPF) of any type occurring where surface temperatures are at or below 29.9°F.
- BFP (Below-Freezing Precipitation), Icy Roads Warning: The amount of precipitation (QPF) of any type occurring where surface temperatures are at or below freezing (32.9°F).
- NFP (Near-Freezing Precipitation), Icy Roads Caution: The amount of precipitation (QPF) of any type occurring where surface temperatures are between 32.9 and 38 degrees Fahrenheit.
- AFP (Above-Freezing Precipitation), No Icing Expected: The amount of precipitation (QPF) of any type occurring where surface temperatures are above 38 degrees Fahrenheit.
The scale used on CIP, BFP, NFP and AFP is zero to 0.1 inches of liquid-equivalent precipitation of any type (rain, snow, sleet, graupel, freezing rain, freezing drizzle, drizzle). Precipitation amounts above 0.1 inches are represented at the same color as 0.1 inches.
Frequently Asked Questions
Why do values increase in a solid line at the 33°, 34° and 35° latitudes?
Icy road risk increases markedly in the southern United States due to decreasing de-icing capacity with southern extent. There are fewer (or no) salt/brine trucks or snowplows to treat and clear roads and bridges in these areas. This means that for any given winter precipitation event, the risk to a driver will be higher in the southern USA than for areas farther north.
Latitude of the data gridpoint is currently the criteria used to assign this increasing risk in southern regions, as it is a good approximation of the actual increase in risk. Since the LCR values are integers, the increase in risk with southern extent must be plotted as a solid line on charts rather than a gradient. Do you have ideas on how this can be better represented on LCR charts? Please let us know!
A high LCR risk was plotted for my area, but nothing happened.
The biggest issue with producing LCR charts is that models currently significantly over-plot the extent of light freezing rain. As freezing rain triggers high risk values, this results in those values being plotted in a few areas that won't experience icing. This is a "model" problem rather than a "LCR" problem, but we are experimenting with ways to filter out as much of these false freezing rain areas as possible. If you are a meteorologist who has ideas on how these can be better filtered, please let us know! We always welcome assistance that can make LCR better and more useful.
It is also important to note that these charts are currently generated by automated computer models. These models are almost never perfect in their depiction of weather, especially the more subtle or light precipitation and temperature values that can make a big difference in high road impacts.
If your area is shown in a LCR risk area, it means the models are plotting conditions favorable for icy roads if the forecasted precipitation actually does occur. Educational Winter Driving Videos - Watch for Free:
  
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1,836
Average annual
deaths in the US
from icy roads
136,309
Average annual
injuries in the US
from icy roads
[ More Statistics ]
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