Flying Weather

 

 

Percent hours with Marginal Visual Flight Rules (MVFR) Conditions:
ceilings less than 5000 ft and/or visibility less than 5 miles
Hour Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
00 39 37 36 29 21 14 13 18 22 26 43 46 29
03 40 40 38 32 24 19 19 27 31 29 45 47 32
06 41 42 41 36 27 27 28 40 43 36 47 48 38
09 43 42 41 36 29 25 21 29 38 35 50 49 36
12 36 37 38 35 31 26 22 25 34 33 47 46 34
15 36 33 38 35 30 23 19 22 29 29 45 43 32
18 36 35 36 30 22 16 12 15 22 26 42 44 28
21 37 34 35 28 20 14 12 15 20 25 42 46 27
ALL 38 37 38 33 26 21 18 24 30 30 45 46 32

 

 

Percent hours with Instrumentation Flight Rules (IFR) Conditions:
ceilings less than 1000 ft and/or visibility less than 3 miles
Hour Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
00 12 10 10 6 3 2 2 4 5 6 10 14 7
03 13 13 12 8 5 4 5 9 13 7 11 15 10
06 13 15 15 12 10 11 13 21 22 11 12 16 14
09 16 18 15 11 6 4 5 9 14 11 16 20 12
12 13 11 11 6 3 2 2 3 5 5 13 16 7
15 11 8 10 4 3 1 1 3 3 4 10 14 6
18 11 9 10 5 3 1 1 2 4 3 8 12 6
21 10 8 10 4 3 1 1 2 3 4 8 12 6
ALL 12 12 12 7 4 3 4 7 9 6 11 15 8

 

 

Pressure

 

 

 

 

 

Average Sea Level Pressure in Millibars by Month and Hour (1948-1992)
HR Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann.
00 1020.1 1020.0 1017.0 1015.3 1014.3 1013.6 1015.3 1016.1 1016.9 1017.5 1017.2 1019.0 1016.8
03 1020.2 1019.9 1016.7 1015.1 1014.3 1013.5 1015.3 1016.0 1016.9 1017.4 1017.0 1019.0 1016.8
06 1020.3 1020.0 1017.2 1015.4 1015.2 1014.3 1015.8 1016.5 1017.5 1017.8 1017.1 1019.1 1017.2
09 1021.0 1020.7 1017.7 1015.8 1015.4 1014.5 1016.1 1016.8 1018.0 1018.3 1017.8 1019.8 1017.7
12 1020.3 1020.3 1017.2 1015.1 1014.7 1014.1 1015.6 1016.3 1017.3 1017.5 1017.1 1019.1 1017.0
15 1019.3 1019.0 1016.0 1014.1 1013.6 1013.1 1014.7 1015.3 1016.1 1016.3 1016.3 1018.3 1016.0
18 1019.9 1019.5 1016.2 1014.0 1013.3 1012.7 1014.2 1014.9 1016.0 1016.7 1016.9 1019.0 1016.1
21 1020.2 1019.9 1016.9 1014.9 1014.4 1013.6 1015.2 1015.9 1016.9 1017.3 1017.1 1019.1 1016.7
Ave 1020.2 1019.9 1016.9 1014.9 1014.4 1013.6 1015.2 1015.9 1016.9 1017.3 1017.1 1019.1 1016.8

 

 

Average Sea Level Pressure in Inches of Mercury (Hg) by Month and Hour (1948-1992)
HR Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann.
00 29.369 29.366 29.294 29.248 29.241 29.227 29.276 29.295 29.315 29.319 29.298 29.346 29.299
03 29.373 29.362 29.286 29.243 29.241 29.224 29.274 29.292 29.314 29.319 29.294 29.347 29.297
06 29.371 29.368 29.298 29.262 29.265 29.247 29.295 29.312 29.333 29.332 29.300 29.344 29.311
09 29.393 29.388 29.314 29.273 29.271 29.253 29.302 29.321 29.346 29.348 29.319 29.364 29.324
12 29.375 29.377 29.300 29.254 29.252 29.241 29.289 29.306 29.328 29.327 29.300 29.346 29.308
15 29.346 29.342 29.266 29.224 29.222 29.214 29.263 29.277 29.293 29.293 29.279 29.323 29.279
18 29.360 29.353 29.272 29.221 29.211 29.201 29.249 29.264 29.290 29.302 29.294 29.340 29.280
21 29.369 29.365 29.289 29.246 29.233 29.218 29.266 29.286 29.311 29.317 29.304 29.347 29.296
Ave 29.369 29.365 29.290 29.246 29.242 29.228 29.277 29.294 29.316 29.320 29.299 29.345 29.299

 


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