Louisiana Winter Storm (Ice, Sleet, Snow)

This interactive tool shows normal (1991-2020) annual and monthly snowfall, average annual number of days with snow totals at certain thresholds, average first and last snow date, and record 1-day snowfall. The map displays normal values while the graph below it shows the variable by year.

1. Position map to area of interest or choose LA in the State Selection drop-down menu on the right. 2. On the top of the screen, select a variable you’re interested in (e.g., Annual Snowfall). Some variables have options on the right side of the screen to select, such as a month to display for monthly snowfall or a snow threshold. 3. For most variables, the map displays the normal/average value for the variable you selected. For Record 1- Day Snowfall, it shows the record value at each point. The legend for the colored points is on the top-right side of the screen. 4. The graph below the map shows more details, such as the values per year instead of an average. Note: The map default shows stations with data from at least 1991-2020. If you’d like to see longer time frames, you can move the slider under the Data Available Since option on the right. When you select a different start year, it will only show stations with available data.

This interactive static map shows the 1-day, 2-day, and 3-day snowfall maximums by parish.

1. Select the day-length of interest on the top right side of the map. 2. Click on the parish of interest for information on the maximum snowfall event on record for your selected time period. 3. A table below the map shows location (by parish and station), date of event, and snowfall total details. Click the top of the right two columns to sort by date or value.

This page includes information about ice storms, including frequency maps of the average annual number of days and hours with freezing rain. Other resources and information, such as preparedness actions, are provided as well.

1. Under the webpage’s heading, click the Frequency tab or scroll down until you reach the section The Frequency of Freezing Rain. 2. View the top map for the average annual number of days with freezing rain from 1948-2000 or the bottom map for the annual average number of hours with freezing rain from 1932-2001. Note: These maps were derived from the journal articles Changnon and Karl (2003) and Changnon (2004). Changnon and Karl (2003) is an open access article and can be found here for further information.

This is a figure within a scientific journal article. While the article includes complex scientific information about the meteorological processes behind ice storms, the analysis in Figure 1 shows a climatology of freezing rain and long-duration freezing rain events from 1979-2016 at stations across North America.

1. Scroll down to Figure 1, located in section 3. Regional climatology of long-duration freezing rain. 2. Click View Full Size under Figure 1 to enlarge the image. 3.  There are 4 maps, including a) median annual freezing rain hours, b) median annual LD (long-duration) freezing rain events, c) percentage of events that are LD (long-duration), and d) number of freezing rain events lasting at least 18 hours from 1979-2016. 4. Each dot on the map represents a weather station. You can view the station closest to your area or read below for a summary of the state.

Figure summary for Louisiana: In map A, we see that most stations across Louisiana do not typically experience freezing rain each year, with the exemption of northern Louisiana that has observed fewer than 10 hours of freezing rain per year. In addition, map B indicates that stations in Louisiana do not typically experience long-duration freezing rain events (or an event lasting more than 6 hours). When freezing rain events do occur, map C shows that 20-50% of events in Louisiana have a long duration. A station in northeast Louisiana observed 40-50% of events as long-duration, which is disproportional to the lack of hours with freezing rain per year. This same station also observed 2-4 freezing rain events lasting at least 18 hours from 1979-2016, shown in map D. Events of this duration are considered in the 99^th percentile, which is a rarity. Other stations across the state observed 2 or fewer events. Overall, this figure shows that much of Louisiana has observed few (if any) hours of freezing rain per year; however, when freezing rain does occur, it can be a long duration. This impacts travel, energy, infrastructure, and health.