Today my minimum temperature of 33° was 5° higher than that at MPO, which was 28°. Below is the Hobo Temp data from logger B (note the 29B along the abscissa):

On it, I labeled the progression of weather events during this day when a warm front ahead of a Low to the NW passed our region. Some clearing occurred after midnight, and temperatures decreased - yet not nearly so much as at MPO (which may still have had a small snow cover). Some heating occurred during morning, though with skies basically cloudy, then a brief period of clearing caused a spike of 41° at 1047 EST. A rain band ahead of the warm front passed our region midday to mid afternoon, temperatures decreasing to 34-33° with fog directly ahead of the front. Warmer SW breezes then occurred after the frontal passage. The question mark means I am not sure what caused the temperature to decrease abruptly around 1725 EST. That is right near sunset, yet skies were cloudy and dark well before that. Sometimes even after the frontal passage, winds from the plateau to the W can temporarily abate and cool air settle here. Regardless, we were clearly in the warm sector late PM - a rain shower causing a brief temperature decrease around 2120 EST. Both MPO & my location got .06 inches of rain with that shower and a daily total of .20 inches. Many of the features mentioned above can also be seen in the MPO observations:

KMPO 290453Z AUTO 28008KT 10SM BKN120 05/M04 A3010 RMK AO2 SLP205 T00501039 400891006 TSNO=
KMPO 290553Z AUTO 27006KT 10SM FEW120 04/M04 A3007 RMK AO2 SLP193 T00391044 10061 20028 58016 TSNO=
KMPO 290653Z AUTO 35003KT 10SM SCT090 02/M04 A3004 RMK AO2 SLP186 T00221044 TSNO=
KMPO 290753Z AUTO 00000KT 10SM CLR M02/M05 A3002 RMK AO2 SLP182 T10171050 TSNO=
KMPO 290853Z AUTO 05003KT 10SM FEW085 M02/M05 A3002 RMK AO2 SLP180 T10221050 56016 TSNO=
KMPO 290953Z AUTO 00000KT 10SM FEW085 M02/M05 A2999 RMK AO2 SLP172 T10171050 TSNO=
KMPO 291053Z AUTO 11004KT 10SM FEW100 01/M04 A2997 RMK AO2 SLP164 T00111044 TSNO=
KMPO 291153Z AUTO 10006KT 10SM SCT085 04/M05 A2995 RMK AO2 SLP155 T00391050 10039 21022 56020 TSNO=
KMPO 291253Z AUTO 10009KT 10SM BKN120 04/M04 A2992 RMK AO2 SLP144 T00391044 TSNO=
KMPO 291353Z AUTO 11007KT 10SM FEW110 04/M04 A2990 RMK AO2 SLP137 T00391044 TSNO=
KMPO 291453Z AUTO 13007KT 10SM FEW100 03/M04 A2990 RMK AO2 SLP139 T00331044 55016 TSNO=
KMPO 291553Z AUTO VRB03KT 10SM FEW055 SCT080 03/M04 A2986 RMK AO2 PRESFR SLP124 T00331044 TSNO=
KMPO 291653Z AUTO 16006KT 10SM -RA BKN049 OVC060 03/M03 A2982 RMK AO2 RAB51 SLP110 P0000 T00281033 TSNO=
KMPO 291753Z AUTO 15008KT 7SM -RA BKN034 OVC048 02/M01 A2978 RMK AO2 PRESFR SLP098 P0001 60001 T00221011 10044 20022 56040 TSNO=
KMPO 291853Z AUTO 12008KT 3SM -RA BR BKN007 BKN016 OVC041 01/00 A2969 RMK AO2 PRESFR SLP069 P0005 T00110000 TSNO=
KMPO 291953Z AUTO 14009KT 1/4SM -RA FG VV001 02/01 A2965 RMK AO2 SLP057 P0006 T00220011 TSNO=
KMPO 292053Z AUTO 18011KT M1/4SM FG VV001 04/03 A2963 RMK AO2 RAE52 SLP050 P0001 60012 T00390033 56047 TSNO=
KMPO 292153Z AUTO 27004KT 1SM BR OVC001 05/04 A2965 RMK AO2 RAB20E35 SLP055 P0001 T00500044 TSNO=
KMPO 292253Z AUTO 22008KT 9SM OVC003 06/04 A2965 RMK AO2 CIG 003V008 SLP054 T00560044 TSNO=
KMPO 292353Z AUTO 23009KT 1 1/2SM BR OVC001 06/05 A2965 RMK AO2 RAB10E31 SLP051 P0000 60013 T00610050 10061 20011 51006 TSNO=
KMPO 300053Z AUTO 25008KT 2 1/2SM BR OVC001 06/05 A2965 RMK AO2 SLP051 T00610050 TSNO=
KMPO 300153Z AUTO 25008KT 1 3/4SM BR OVC001 06/06 A2966 RMK AO2 SLP054 T00610056 TSNO=
KMPO 300253Z AUTO 26006KT 9SM -RA SCT005 SCT016 BKN045 06/05 A2966 RMK AO2 RAB21 SLP055 P0006 60006 T00610050 53003 TSNO=
KMPO 300353Z AUTO 27009KT 10SM FEW085 06/04 A2967 RMK AO2 RAE0256 SLP056 P0000 T00610044 TSNO=
KMPO 300453Z AUTO 27009KT 10SM CLR 06/04 A2967 RMK AO2 SLP058 T00560044 400611022 TSNO=

Regarding the minimum, below are plots from both loggers side-by-side:

Note again how they match very closely. MPO reported clear skies and calm winds at 0753 Z, which is 0253 EST. Their temperature was 29° - a 7° decrease from the previous hour with a northerly breeze. That sort of thing generally does not happen here along the slope. My minimum of 33° occurred at 0300 EST, which was only 2° cooler than the 0200 EST temperature of 35° - though the temperature went as high as 37° at 0240-0245 EST. So actually there was a 4° decrease over a period of about 15 minutes. The data points for this set were every 15 seconds, and the lowest 75 second average (5 points) was 32.994°. The lowest 5-minute average was 33.31° during the afternoon period of fog directly ahead of the warm front. That is because a reading of 33.31° occurred over an extended period, with a few points directly above at 34.10°:

So even if there was no error, because of the resolution of the instrument the afternoon minimum may not have been below 33.5°.

I won't generally issue a report of this sort every day, though because I am currently comparing the 2 loggers I thought this may be interesting - the difference of minima something which often occurs during calm & clear nights.

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