Castle Airport

KMER / MER

Merced, US

Last Updated
Apr 21, 21:55Z

Current Weather

Display Units
Aging 1 hour ago
21:55Z

🌙 Night
MVFR
Flight Rules
--
Temperature
Dewpoint: --
9 kt
190°
3 SM
Visibility
4,400 ft
Ceiling
Above Ground Level
--
QNH
Altimeter Setting

Raw METAR

METAR KMER 212155Z 19009KT 3SM RA FEW035 BKN044 OVC060

Clouds - Visual Profile

12,000ft
9,000ft
6,000ft
3,000ft
Ground
Field Elev: 191 ft
FEW 3,500 ft AGL
BKN 4,400 ft AGL
OVC 6,000 ft AGL
🌤️
FEW
Few (1/8-2/8 sky coverage)
3,500 ft
AGL (Above Ground)
3,691 ft AMSL
☁️
BKN
Broken (5/8-7/8 sky coverage)
4,400 ft
AGL (Above Ground)
4,591 ft AMSL
☁️
OVC
Overcast (8/8 sky coverage)
6,000 ft
AGL (Above Ground)
6,191 ft AMSL

Weather Briefing

MVFR

Castle Airport is currently reporting marginal VFR (MVFR) conditions with overcast skies at 6,000 feet and 3 SM visibility. Note: This observation is 1 hours old and conditions may have changed.

Wind Analysis

Winds are from the south (190°) at 9 knots. Runway 13/31 is favored with a 5-knot headwind and 8-knot crosswind component.

Visibility & Ceiling

Visibility is 3 SM, below VFR minimums in some airspace classifications. Check local requirements before departing VFR. The ceiling is 4400 feet AGL (broken), well above standard VFR minimums.

Temperature & Moisture

Temperature data is not available.

Forecast Outlook

The TAF forecast covers the next 22 hours. Conditions are expected to fluctuate between VFR and MVFR. VFR pilots should be prepared for deteriorating conditions. Expected weather includes: Light Rain, Light Thunderstorm Rain, Mist. Temporary MVFR conditions are forecast with Light Thunderstorm Rain, Mist between 21:00Z and 01:00Z.

Pilot Recommendations

VFR pilots should exercise caution. Consider filing IFR if instrument rated, or postponing the flight if conditions are expected to deteriorate further.

This briefing is generated from real-time METAR and TAF data. Always verify with official sources before flight.

Forecast (TAF)

View Full TAF
Raw TAF
TAF KMER 212003Z 2120/2218 11010KT P6SM -RA SCT007 OVC050 TEMPO 2121/2201 VRB12G22KT 3SM -TSRA BR OVC040CB FM220100 22010G19KT P6SM -RA OVC050 FM220600 29007KT P6SM -RA SCT050 OVC120 FM221000 VRB05KT P6SM SCT050 BKN100 AMD NOT SKED
Upcoming Changes (Next 12 Hours)
22:57Z BASE
+0h
VFR 110° 10 kt
Visibility: >6SM
Ceiling: 5,000 ft
Light Rain
01:00Z FM220100
+3h
VFR 220° 10 kt
Visibility: >6SM
Ceiling: 5,000 ft
Light Rain
06:00Z FM220600
+8h
VFR 290° 7 kt
Visibility: >6SM
Ceiling: 12,000 ft
Light Rain
10:00Z FM221000
+12h
VFR VRB 5 kt
Visibility: >6SM
Ceiling: 10,000 ft

24-Hour Weather Evolution

Loading weather data...
Data Sources
  • • Current conditions from METAR observations
  • • Historical data from past 24 hours
  • • No forecast or predicted data included
  • • Data updated with each new METAR report
Chart Features
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Note: Future values beyond current TAF validity are estimates based on climatological data and trends. Always verify with current forecasts before flight operations.

Airport Runway Layout

N
MER
13 ✈️
31

Runway Information

Runway Length Width Surface Heading Wind Component
✈️ 13/31
Active: 13
11,802 ft 150 ft PEM 141°
4.5 kt 7.8 kt
60° angle
🟢 Active Runway: Best headwind component for current conditions
⬆️ Headwind: Favorable wind component
↔️ Crosswind: ≤10kt Safe, 11-15kt Caution, >15kt Challenging

Weather Statistics - KMER

1,430 observations | Oct 2025 - Apr 2026

Flight Rules Distribution

VFR
72.9%
MVFR
12.7%
IFR
7.3%
LIFR
7.1%

Castle Airport typically experiences VFR conditions 72.9% of the time, though instrument-rated pilots will find IFR weather present approximately 14.4% of observations. Prevailing winds are from the NW averaging 10.8 knots, with gusts recorded up to 108 knots. Calm conditions occur 50% of the time. Temperatures typically range between 6°C and 26°C with an average of 10.3°C. Fog is a notable factor, occurring in approximately 10.3% of observations, with visibility below 3 SM in 7.3% of reports. The best months for VFR flying are October, March, April.

Wind Analysis

Prevailing Direction: NW (315°)
Average Speed: 10.8 kt
Maximum Recorded: 108 kt
Calm Winds: 50%
Direction Distribution:
N
12.6%
NE
0.1%
E
0.6%
SE
12.2%
S
6%
SW
0.7%
W
2%
NW
15.9%

Temperature Range

Average: 10.3°C
Range: 6°C to 26°C
6°C 26°C

Visibility

Average: 8 SM
Below 3 SM: 7.3%
Fog Frequency: 10.3%

Best Months for VFR

October March April

Runway Wind Analysis

Runway 13/31
Favorable wind: 100%
Avg crosswind: 4.7 kt

Statistics computed from 1,430 METAR observations (Oct 2025 - Apr 2026). Data sourced from official aviation weather services. Updated daily.

Castle Airport - Airport Information

Airport Details

ICAO Code: KMER
IATA Code: MER
Type: medium airport
Status: active
Elevation: 191 ft MSL

Location

City: Merced
Country: US
Latitude: 37.380501°
Longitude: -120.568001°
Time Zone: Etc/GMT+8

Runway Information

Runway 13/31
Length: 11,802 ft
Width: 150 ft
Surface: PEM
ILS: No

About Castle Airport

Overview

Castle Airport serves the Merced area in California's Central Valley, positioned at 191 feet above mean sea level. As a medium-sized airport with a substantial 11,802-foot primary runway (13/31), it supports diverse aviation operations in a strategic regional location.

Flying Conditions

Weather conditions at Castle Airport demonstrate significant variability, with Visual Flight Rules (VFR) prevailing in 56.6% of observations. Pilots should anticipate potential instrument meteorological conditions, with 15.7% IFR and 15.2% Low IFR periods, particularly during transitional seasons. Temperatures range from 6°C to 26°C, with an average of 10.3°C.

Notable Features

The airport experiences predominantly southeast winds at 135 degrees, averaging 11.6 knots with occasional gusts up to 25 knots. Visibility averages 6.4 statute miles, with 16.5% of observations showing reduced visibility and 15.8% experiencing fog conditions. Calm wind periods are frequent, occurring in 67.9% of recorded observations.

Approach Considerations

Runway 13/31 offers favorable wind alignment 100% of the time, with an average crosswind component of just 4.5 knots. October, January, and December represent the most consistently favorable VFR months for aviation operations. Pilots should prepare for potential visibility restrictions and be prepared to utilize instrument procedures during less predictable weather periods.

Data Sources & Accuracy: Airport information sourced from OurAirports.com, a collaborative database of worldwide airport data. Weather data from official aviation weather services including NOAA Aviation Weather Center and international METAR/TAF providers. Information is updated regularly but pilots should always verify current conditions and NOTAMs through official channels before flight operations.

Official Data Sources

Weather NOAA Aviation Weather Center • International METAR/TAF Network
Airports OurAirports.com • Public domain airport database
NOTAMs FAA NOTAM System • ICAO NOTAM Distribution
Last updated: Jan 1, 1970 12:00 AM UTC

Disclaimer: Data is provided for informational purposes only. Pilots must verify all information through official sources before flight operations. Weather conditions change rapidly; always obtain a current briefing from approved weather services.