Fall Freeze Feature

Fall Freeze Data For New Mexico

The growing season across New Mexico varies considerably, due to the large variation in elevation. The lowest elevations are near 3,000 feet in the far southeast plains (around Jal), while the highest elevations tower above 13,000 feet (Wheeler Peak). The San Juan, Rio Grande, Canadian and Pecos river valleys also affect the growing season, as cold air sinks into the valleys on many fall and winter nights. See the graphic example farther below. To complicate matters, there is often what is called a 'thermal belt' above the cold pool of air in the valley. This is a layer of air that is considerably warmer than farther below in the valley. This thermal belt is usually located near the mid slope of a mountain or more gently sloping terrain. A good example exists around Albuquerque. At the valley floor, temperatures can be ten or more degrees colder than at the Albuquerque Sunport, while the Sunport will generally be several degrees warmer than the foothills.

A 'freeze' is considered to have occurred whenever the temperature drops to 32° or lower. A growing season is calculated by taking the number of days between the last freeze in the spring and the first freeze in the fall. However, plants or crops do not necessarily follow this rule. A low temperature of 31 or 32° for a short period of time, say less than two hours, probably will not harm most plants or crops. But if the temperature drops to 28 or 29° for a few hours, most vegetation will be damaged. As a side note, frost can form when a solid surface (like a car or plants) is in contact with the air and the solid surface's temperature drops to 32° or colder. The extent of the frost depends on how much moisture is in the air. If the temperature is above 32° and there is enough moisture in the air, then dew (a liquid) forms instead of frost (a solid).

Place your cursor over a green circle on the map below to view probabilistic freeze data for locations across New Mexico, including the 90th, 50th (average), and 10th percentiles for 32° and 28°.

An extensive list of fall freeze data for select locations in New Mexico has been compiled using the NCEI summary of annual agricultural normals for the period 1991-2020.

Map of New Mexico With Freeze Data Locations

Map of Freeze Program Forecast Zones

Not all of the 41 forecast zones within the Albuquerque National Weather Service county warning area receive freeze warnings during the fall season. The map below outlines areas in light blue where freeze warnings are issued during the fall season. There are two main reasons why not every forecast zone in our county warning area receive freeze warnings. The primary reason a forecast zone does not receive a freeze warning is that a freeze is possible at any time of year for mountain zones and for elevated plateaus of northern and western New Mexico. The secondary reason is portions of New Mexico do not, and cannot, support significant agricultural production due to the intense desert climate and lack of irrigation.

The table below highlights the average number of days for the growing season around the Albuquerque metro area (average number of days between the last freeze in the spring and first freeze in the autumn each year.)


Average Growing Season Albuquerque Metro Area
Location	Average Days
Albuquerque Sunport	210
Albuquerque Foothills	193
Albuquerque South Valley	187
Sandia Park (inactive station)	174
Los Lunas 3 SSW	171
Corrales	161
Moriarty	144


Albuquerque Metro Area Recent First Fall Freeze Dates
Location	2021	2020	2019	2018	2017	2016
Albuquerque Sunport	Nov. 18	Oct. 26	Oct. 25	Nov. 9	Nov. 19	Nov. 18
Albuquerque Foothills	n/a	n/a	n/a	Oct. 16	Nov. 18	n/a
Albuquerque South Valley	Oct. 13	Oct. 26	Oct. 11	Nov. 4	Oct. 29	Nov. 13
Los Lunas 3 SSW	Oct. 13	Oct. 27	Oct. 11	Oct. 16	Oct. 29	Oct. 5
Corrales	n/a	Oct. 22	Oct. 11	Nov. 2	Oct. 21	Oct. 19

Preparing for Freezing Temperatures

Preparing for the first fall freeze should take place during late summer and early fall while it's still mild outside. Fall weather in New Mexico varies considerably from September to October with periods of warm and tranquil weather followed by cold, unsettled conditions then periods of mild and pleasant weather once again. The growing season ends by late September over mountain locations but may continue into early November if conditions remain mild over southern areas and the eastern plains. While many deciduous plants are shedding leaves, cool season gardening may continue through late October until the sun angle gets too low to provide any worthwhile growth. The large diurnal spread from mild daytime highs to cold morning lows can send the avid gardener into a frenzy of activity protecting outdoor plants, covering spigots, and storing garden hoses one day only to be pulled out the next. Eventually, cold nights will ensue on a daily basis once we progress through the fall season and there are several things to prepare for before it gets too cold.

Winterize your home to prepare for the upcoming winter season. Here are some recommended tips to prepare for freezing temperatures.

Power down swamp coolers, turn off the water supply, cover with protective materials, and secure units from high winds.
Insulate shelters for livestock and pets if your animals will spend any time outside in the freezing cold.
Cover outdoor spigots with insulating material and store garden hoses in a safe manner to avoid tripping hazards.
Clean and store outdoor tools and gardening equipment.
Winterize rain barrels and clean gutters.
Organize the garage and tidy up the yard.
Restock your supplies of sand and ice melt.
Plan your resources to stay warm this winter (i.e., propane, wood, wood pellets, gas, electric heaters, etc.).
Prepare your vehicle for the winter and refresh emergency kits.
Prepare your garden for next spring. Some grasses and garden beds may like an application of fertilizer to wake up to in the spring. Check with your local gardening expert on recommendations for specific plants.

Enjoy all the beautiful outdoor activities New Mexico has to offer as we progress through the fall season!

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