1 May, 2003

April South Pole Weather Report

Monthly Climate Summary for April 2003

South Pole Station, Antarctica

Temperature:

Average temp............ -56.7イ / -70.1ェ Departure from normal... +0.8イ / +1.4ェ

Maximum temp............ -40.1 イ / -40.2ェ on day 9 Minimum temp............ -69.3 イ / -92.7ェ on day 7

Wind:

Average wind speed.......... 12.0 mph or 10.4 knots Prevailing wind direction... Grid North or 360 degrees Maximum wind speed.......... 32 mph or 28 knots on day 30 Maximum wind direction...... Grid North

Average vectored wind....... 042 degrees at 7.8 knots

Station Pressure:

Average pressure........ 677.1 mb or 19.995 in. Hg Departure from normal... -3.3 mb or -0.097 in. Hg Highest pressure........ 689.0 mb or 20.346 in. Hg on day 09 Lowest pressure......... 661.7 mb or 19.540 in. Hg on day 18

Physio-altitude:

Average Physio-alt = 10738 ft / 3273 m

Highest Physio-alt = 11326 ft / 3452 m

Lowest Physio-alt = 10291 ft / 3137 m

Sky Cover:

Average cloud cover (8ths)... 04

Days clear................... 11

Days partly cloudy........... 12

Days cloudy.................. 07

Sunshine:

Sunrise on 21 September 2003

Average hours per day... 0.0

Percent of possible..... 0

Visibility... 7 days with a visibility of 1/4 mile or less.

Snowfall..... TRACE; average net change at snow stakes -0.626 inches.

Balloon flight data:

Number of soundings for the month... 30

Average height of sounding.......... 52.0 mbs or 20211 meters above msl Highest sounding.................... 9.0 mbs or 30234 meters above msl on the day 05/00Z sounding

Remarks:

00 soundings were missed.

14 soundings were terminated above 50 mbs.

16 soundings were terminated between 50 and 100 mbs. 00 soundings were terminated below 100 mbs.

**RECORDS**

Day 9 - The maximum temperature of -40.1 C/-40.2 F broke the previous record high of -43.3 C/-45.9 F set in 1970.

Day 14 - The peak wind speed of 27 kts/31 mph ties the previous record set in 1999.

Day 21 - The maximum temperature of -40.4 C/-40.7 F broke the previous record high of -42.4 C/-44.3 F set in 1983.

Day 22 - The peak wind speed of 27 kts/31 mph broke the previous wind record of 26 kts/30 mph set in 2001.

PREPARED BY: K. Hess