Bat Hot Spring, Pence Hot Spring

Elmore County, Idaho · Near Mountain Home Air Force Base
42.7970°N, 115.7230°W · 2,590 ft
117°F 41°F air · Good soaking weather 2,590 ft Short Walk
Aerial view of the ground around Bat Hot Spring, Pence Hot Spring LiDAR bare-earth view of the same ground around Bat Hot Spring, Pence Hot Spring
Aerial LiDAR bare earth

Drag the handle to compare the two views. The orange dot marks the spring, in a frame about three quarters of a mile wide.

Bat Hot Spring, also listed as Pence Hot Spring, is a hot spring in Elmore County, Idaho, right at Mountain Home Air Force Base by the distance on record, which rounds to zero. The water is hot, above the range most people soak in. Hot Springs Road runs a third of a mile away. Owner and access are not recorded.

Location
0 miles from Mountain Home Air Force Base, ID

Low desert by the numbers: ten inches of precipitation and under a foot of snow, with a warm average year. Elevation is around twenty-six hundred feet. From Hot Springs Road you finish on foot, and the distance is small. The record names no land unit and lists no campground.

Climate puts winter first here, and light snow is less of a barrier. Chemistry is from 1989, alkaline with iron present. The water is hot enough to hurt. Ease in or stay out. No fee listed. Access status is missing, and with an Air Force base this close, find out whose land it is before you go.

Terrain

Aircraft with laser scanners measured this ground to within inches. The scan strips out trees and buildings, leaving the bare shape of the land around Bat Hot Spring, Pence Hot Spring.

Setting
Open ground
Flat, open ground all around.
Highest ground nearby
12 ft above the spring
Within a quarter mile, to the southwest
Cross-section through the spring

A slice through the ground from northwest to southeast, about 0.6 miles end to end.

Elevation data: USGS 3D Elevation Program. Aerial imagery: USGS The National Map. Public domain.

Heat Below
102 milliwatts per square meter of heat flow

That's about 1½ times the US average of 65. It's higher than at 50% of the springs on this site.

Heat flow measures the warmth working its way up through the ground from deep inside the earth. Where it runs high, rain and snowmelt that seep down through cracks in the rock come back up hot.

Heat flow estimate: Stanford Thermal Earth Model (Aljubran & Horne, 2024), CC BY 4.0.

Monthly Climate
32°
Jan
38°
Feb
46°
Mar
54°
Apr
63°
May
73°
Jun
83°
Jul
82°
Aug
70°
Sep
55°
Oct
42°
Nov
32°
Dec
Annual Precip: 9.6 in Annual Snow: 11.4 in
Best Time to Visit
January Air 32°F · Water 117°F · +85° contrast
December Air 32°F · Water 117°F · +85° contrast
February Air 38°F · Water 117°F · +79° contrast
January offers 51°F more contrast than July
Current Conditions
41°F
Clear ENE 33.0 mph 67% Good soaking weather
Today 78° Low 47° Sunny
Spring is +39° warmer
Wednesday 80° Low 52° Sunny
Spring is +37° warmer
Thursday 79° Low 50° Slight Chance Rain Showers 16% precip
Spring is +38° warmer
Friday 78° Low 48° Sunny 5% precip
Spring is +39° warmer
Saturday 80° Low 49° Sunny 5% precip
Spring is +37° warmer
Water Chemistry Sampled 1989-03-08

The water at Bat Hot Spring, Pence Hot Spring is slightly alkaline (pH 8.2) with 243 mg/L total dissolved solids.

pH 8.2 Slightly Alkaline
pH influences mineral absorption through skin
Higher mineral concentration for therapeutic soaking
Calcium 11 mg/L
May support bone density and joint health
Magnesium 1 mg/L
Known for muscle relaxation and stress relief
Sodium 49 mg/L
Supports circulation and skin hydration
Sulfate 20 mg/L
Traditionally used for skin conditions and inflammation
Chloride 9 mg/L
Natural antiseptic with skin health benefits
Iron 50 µg/L
Iron-rich springs may support circulation
Temperature
117°F
Warm Hot Boiling
Water Temp 117°F (47°C)
Avg Air Temp 56°F
Above Ambient +61°F
Good soaking conditions September
Access
Road Access Short Walk
Nearest Road Hot Springs Road
Distance to Road 0.3 mi
Frequently Asked Questions
What is the water temperature at Bat Hot Spring, Pence Hot Spring?
Bat Hot Spring, Pence Hot Spring has a water temperature of 117°F (47°C). This is considered a hot spring, well above body temperature.
Where is Bat Hot Spring, Pence Hot Spring located?
Bat Hot Spring, Pence Hot Spring is located in Elmore County, Idaho at 2,590 feet elevation, near Mountain Home Air Force Base. Coordinates: 42.7970°N, 115.7230°W.
How do I get to Bat Hot Spring, Pence Hot Spring?
Bat Hot Spring, Pence Hot Spring has Short Walk road access, with the nearest road being Hot Springs Road (0.3 mi from the road).
What minerals are in the water at Bat Hot Spring, Pence Hot Spring?
Water chemistry analysis shows the presence of pH, Total Dissolved Solids, Calcium, Magnesium, Sodium, Sulfate, Chloride, Iron. The pH is 8.2 (slightly alkaline). Total dissolved solids measure 243 mg/L.
Is it safe to soak at Bat Hot Spring, Pence Hot Spring?
With care. At 117°F Bat Hot Spring, Pence Hot Spring is hot enough to need short sessions, fifteen to twenty minutes, and plenty of water. Enter slowly and get out if you feel light-headed.
Sources: USGS NWIS