Hennessey, Oklahoma climate: Normal weather by month, frost dates and records

Hennessey's normal year runs from 24°F January nights to 95°F July afternoons, with 33.5 inches of precipitation and 9 inches of snow a year. (NOAA 1991-2020 normals)

In metric: a yearly mean of 14.8°C, January lows of −5°C, July highs of 35°C, 850 mm of precipitation a year.

  • NOAA stationHennessey (4 mi ESE)
  • Station IDUSC00344055
  • Location36.09°N 97.83°W
  • Elevation1,174 ft (358 m)
  • From the center4 miles
  • Population2,223

On October 23, the normal high in Hennessey is 70°F and the normal low 44°F, and the chance of measurable rain or snow is 19%.

Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Hennessey.

  1. Jan 47° 24°
  2. Feb 51° 27°
  3. Mar 61° 35°
  4. Apr 70° 44°
  5. May 79° 55°
  6. Jun 90° 65°
  7. Jul 95° 70°
  8. Aug 94° 68°
  9. Sep 85° 60°
  10. Oct 73° 47°
  11. Nov 59° 35°
  12. Dec 48° 26°

Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.

What is the weather like in Hennessey each month?

July is the warmest month, with normal highs of 95°F; January the coldest, with normal lows of 24°F. The most precipitation falls in May (5.03 in), the least in January (1.25 in).

Hennessey monthly normals, 1991-2020 (°F, inches)
MonthHighLowMeanPrecip.SnowWet days90°F daysFreezing nightsDaylight
January 47°F24°F35.5°F 1.253.1 4<12610 h
February 51°F27°F39.0°F 1.441.6 5<11910 h 50 min
March 61°F35°F47.8°F 2.511.2 7<11111 h 50 min
April 70°F44°F56.7°F 3.530.0 71313 h
May 79°F55°F67.2°F 5.030.0 94<114 h
June 90°F65°F77.6°F 4.480.0 816<114 h 40 min
July 95°F70°F82.4°F 3.000.0 625<114 h 20 min
August 94°F68°F80.7°F 3.490.0 623<113 h 30 min
September 85°F60°F72.7°F 2.260.0 510<112 h 30 min
October 73°F47°F60.0°F 2.930.0 61111 h 20 min
November 59°F35°F47.0°F 1.830.4 5<11110 h 20 min
December 48°F26°F37.2°F 1.702.8 6<1239 h 40 min
Year (annual)71°F46°F58.7°F33.459.1738094
The same normals in °C and millimetres
Hennessey monthly normals, 1991-2020 (°C, mm, snow in cm)
MonthHighLowMeanPrecip.Snow
January8°C−5°C1.9°C32 mm8 cm
February11°C−3°C3.9°C37 mm4 cm
March16°C2°C8.8°C64 mm3 cm
April21°C7°C13.7°C90 mm0 cm
May26°C13°C19.6°C128 mm0 cm
June32°C19°C25.3°C114 mm0 cm
July35°C21°C28.0°C76 mm0 cm
August34°C20°C27.1°C89 mm0 cm
September30°C16°C22.6°C57 mm0 cm
October23°C8°C15.6°C74 mm0 cm
November15°C2°C8.3°C46 mm1 cm
December9°C−3°C2.9°C43 mm7 cm
Normal daily high and low by month, Hennessey
Normal precipitation by month, Hennessey (inches)

Source: NOAA NCEI 1991-2020 monthly normals, station USC00344055; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.

When is the best weather to visit Hennessey?

Normal highs sit between 65°F and 85°F in April, May and October. Of those, October has the fewest days with rain (6).

That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.

Source: NOAA NCEI 1991-2020 monthly normals, station USC00344055.

When is the last frost in Hennessey?

In Hennessey, the last spring frost (32°F) comes after April 14 in half of years and after April 27 in one year in ten; the first autumn frost comes before October 30 in half of years and before October 17 in one year in ten.

Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years

Last spring frost, half of years after
April 141 year in 10 after April 27; 9 in 10 after March 29
First autumn frost, half of years before
October 301 year in 10 before October 17; 9 in 10 before November 11

NOAA puts the median frost-free season at 198 days, and the season without a hard freeze (28°F) at 218 days.

A hard freeze (28°F) comes after April 2 in half of springs and before November 6 in half of autumns.

The USDA's 2023 Plant Hardiness Zone Map puts Hennessey in zone 7a in ZIP code 73742, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Hennessey's NOAA station is in zone 7a: the coldest night of a typical year reaches 3°F (20 complete years).

Frost dates for every NOAA station in Oklahoma · Frost dates by ZIP code

Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00344055; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.

How hot and how cold does it get in Hennessey?

In a normal year in Hennessey, 80 days a year reach 90°F (23 of them 100°F or more), 94 nights fall to 32°F or colder and 73 days bring measurable precipitation.

Days at 90°F or more
80a normal year
Days at 100°F or more
23a normal year
Nights at 32°F or colder
94a normal year
Days that stay below freezing
11high of 32°F or less
Days with 0.01 inch of precipitation
73a normal year
Days with 1 inch of snow or more
3a normal year

The highest temperature in this station's record (since 1895) is 116°F, on August 24, 1922; the lowest is −20°F, on February 11, 2011.

The wettest calendar year on that record is 1957, with 52.13 in; the snowiest season is 1987–88, with 37.5 inches.

Source: NOAA NCEI 1991-2020 annual normals, station USC00344055; records: ACIS (NOAA Regional Climate Centers), station USC00344055. Records use complete months only; a month missing more than three days is left out.

How sunny is Hennessey?

Over a year 80% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Hennessey, 4.7 kWh per square metre a day. July is the sunniest month (87%) and February the cloudiest (74%).

Hennessey: sunshine by month (NASA POWER, 2001-2020)
MonthShare of clear-sky sunshineSunshine, kWh/m² a day
January77%2.7
February74%3.4
March74%4.4
April76%5.5
May77%6.1
June86%7.0
July87%6.9
August86%6.1
September84%5.1
October80%3.9
November80%2.9
December74%2.3

Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.

How much heating and cooling does Hennessey need?

A normal year in Hennessey brings 4,146 heating degree days, 23% fewer than the median U.S. place (5,373), and 1,868 cooling degree days, 2.1 times the median (908). Five months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 4,778 growing degree days a year above 50°F.

Hennessey: normal heating and cooling degree days by month (base 65°F)
MonthHeatingCooling
January9160
February7280
March5353
April26921
May68135
June2379
July0541
August0485
September22253
October20348
November5422
December8600
Year (annual)4,1461,868

Source: NOAA NCEI 1991-2020 monthly normals, station USC00344055. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.

How does Hennessey's climate compare?

Hennessey is warmer than 21 of the other 133 places with their own NOAA record in Oklahoma, and wetter than 38. Across the 7,247 U.S. stations with normals, its annual mean of 58.7°F is warmer than 71%.

In the Köppen classification computed from these normals, Hennessey is Cfa: temperate, no dry season, hot summer. What the classes mean.

Places with the most similar year elsewhere

Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:

Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.

Which places near Hennessey share this climate record?

2 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.

  • Dover, OK411 people · 9 mi SW
  • Bison, OK54 people · 8 mi NW

Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.

Questions about Hennessey's climate

What is the coldest month in Hennessey?

January, with a normal high of 47°F and a normal low of 24°F. The warmest is July (95°F by day, 70°F at night).

Does it snow in Hennessey?

Yes: 9 inches in a normal year, falling on 4 days with 0.1 inch or more, the most in January (3.1 inches).

What is the rainiest month in Hennessey?

May, with 5.03 in of precipitation in a normal year; the driest is January with 1.25 in.

What plant hardiness zone is Hennessey in?

The USDA's 2023 map puts Hennessey in zone 7a in ZIP code 73742, the nearest ZIP area. By the same method at Hennessey's NOAA station, the coldest night of a typical year reaches 3°F (20 years, 1991-2020): zone 7a.

How late can frost come in Hennessey?

In half of years the last 32°F night comes after April 14; in one year in ten it comes after April 27. Waiting until April 27 leaves about a one-in-ten chance of a later frost.

Nearby and next

Download these normals (CSV) · JSON · How these figures are made