Olympic Climatology

Table of Contents

Overview

Venue Climate

Hazardous Weather

Opening and Closing

CPC Forecast

Forecast Team

Winter Sunrise in Salt Lake City

--photo courtesy Sean Breazeal

Olympic Weather Overview

Weather during the 2002 Winter Olympics and Paralympics will be influenced by a number of factors. The progression of winter storms across the western United States is modulated by the position of the jet stream, which is located roughly 10 km above the earth's surface. The generally west-to-east oriented jet meanders across the western United States due to natural variations in the earth's climate system. Colder and snowier winters in northern Utah usually occur when the jet stream is displaced to the south of its usual position while warmer and drier conditions prevail when the jet is displaced to the north. During the past 2 Olympic periods (February 2000 and 2001), the jet was weak and frequently split into air streams to the north and south of Utah. The net result was wetter than normal conditions during both months while temperatures were above normal in 2000 and near normal in 2001.	photo courtesy SLOC
Weather systems approach northern Utah from all directions and are strongly modulated by the mountain ranges of the western United States. For example, the Sierras and smaller ranges in Nevada to the west impede, distort, and wring moisture from Pacific winter storms while the Rockies to the north and east inhibit Arctic air outbreaks that frequently penetrate further south across the Plains. In the vicinity of the Olympic venues, the Wasatch Mountains of northern Utah are a major barrier to storms crossing the Great Basin. As the air is forced to rise over the Wasatch, precipitation is enhanced. For example, during February, snowfall on average increases from roughly an inch (2.5 cm) over the western deserts to 11 inches (28 cm) in the Salt Lake Valley to over 75 inches (191 cm) near the top of the Wasatch; in the lee of the range, precipitation decreases to 21 inches (53 cm) at Park City. The Great Salt Lake helps to modify local wind circulations and lake-effect snow storms downwind of the lake are common (affecting the Ogden area when the winds are from the west and the Salt Lake Valley when the winds are from the northwest).
photo courtesy SLOC	Along the Wasatch Front from Ogden to Provo, early morning temperatures are typically below freezing (around 25° F/-4° C in February and 30° F/-1° C in March). Rare arctic air outbreaks have led to record cold temperatures below 0° F /-18° C in February. Afternoon temperatures are usually above 40° F/4° C in February and above 50° F/10° C in March with record highs over 65° F/18° C in February and 75° F/24° C in March. Typically, about 5 snow storms occur along the Wasatch Front during February with average snowfall during the month around 11 inches (28 cm). Snow storms are equally likely during the Paralympic period during March. Heavy fog in the valleys is not uncommon, with roughly an 8% chance that fog develops on any particular day in February. Fog episodes arise from stable atmospheric conditions with limited ventilation in the valleys; these conditions also favor poor air quality.
The mountain valleys to the east of the Wasatch Mountains are at higher elevation than the Wasatch Front. Temperatures tend to be significantly lower in the morning (average minimum temperatures around 15° F/ -9° C) due to cold air pooling in the high mountain valleys while afternoon temperatures tend to be around 40° F/ 4° C. The number of storms with precipitation falling as snow rather than rain is slightly higher in the mountain valleys than the number along the Wasatch Front with snowfall amounts varying from 11 inches (28 cm) in the Ogden Valley to 16 inches (41 cm) in the Heber Valley during February.

Venue Climate

Typical weather conditions at the outdoor Olympic venues are summarized in the following tables. Early morning temperatures are on the order of 15°F/-9°C with afternoon temperatures slightly above freezing in February. Snowfall varies significantly with higher precipitation amounts at the downhill course (Snowbasin Ski Area) and significantly less snow at the cross-country venue (Soldier Hollow). At higher elevations on the mountain, temperatures are even lower and precipitation amounts are higher.

Snowbasin Ski Resort
Current Weather Conditions at Snowbasin Base Elevation: 6400 ft, 1950 m
	February	March
High Temperature	36° F, 2° C	44° F, 7° C
Low Temperature	19° F, -7° C	23° F, -5° C
Snowfall	56 in, 142 cm	40 in, 101 cm

Utah Olympic Park
Current Weather Conditions at Utah Olympic Park Base Elevation: 6900 ft, 2100 m
	February	March
High Temperature	34° F, 1° C	43° F, 6° C
Low Temperature	16° F, -9° C	22° F, -6° C
Snowfall	28 in, 71 cm	20 in, 50 cm

Park City Ski Resort
Current Weather Conditions at Park City Base Elevation: 6900 ft, 2100 m
	February	March
High Temperature	37° F, 3° C	47° F, 8° C
Low Temperature	16° F, -9° C	23° F, -5° C
Snowfall	34 in, 87 cm	24 in, 62 cm

Deer Valley Ski Resort
Current Weather Conditions at Deer Valley Base Elevation: 7400 ft, 2255 m
	February	March
High Temperature	33° F, 0° C	41° F, 5° C
Low Temperature	17° F, -8° C	23° F, -5° C
Snowfall	34 in, 87 cm	24 in, 62 cm

Soldier Hollow
Current Weather Conditions at Soldier Hollow Elevation: 5600 ft, 1700 m
	February	March
High Temperature	37° F, 3° C	44° F, 7° C
Low Temperature	6° F, -9° C	24° F, -4° C
Snowfall	19 in, 48 cm	12 in, 30 cm

All Venue Photos Courtesy of SLOC.

Hazardous Weather Summary
During the Olympic and Paralympic period, winter storms can usher in a variety of hazardous conditions: low temperatures, heavy snowfall, and high winds are common. Record snowfall in a 24 hour interval during the Olympic period varies from over 10 inches (25 cm) along the Wasatch Front to over several feet (100 cm) in the mountains. Downslope wind storms with winds in excess of 40 mph/65 kph occasionally develop immediately to the west of the Wasatch Range (within a mile/2 km of the base of the mountains). There is an 8% chance that winds in excess of 40 mph/65 kph could affect Opening and Closing Ceremonies on the University of Utah campus and strong winds are also possible, for example, at the Park and Ride facility near the mouth of Weber Canyon. Significant weather that has occurred during past Olympic and Paralympic periods.	photo courtesy SL Tribune

Likely Weather Conditions during Opening and Closing Ceremonies
Based on evaluation of hourly reports from February 5-25 1972-2001 at Salt Lake City Airport, daily reports at Hogle Zoo, and hourly reports at the University of Utah.
There is a 30% chance of having "weather" (rain, snow, or fog) during a four hour ceremony. There is a 20% chance of having precipitation (rain, snow, or rain/snow) for at least one hour of a four hour ceremony. If precipitation is falling during a four hour ceremony, there is only a 6% chance that it will persist through the whole ceremony. There is a slightly better chance of it snowing than raining during the ceremonies. There is a 10% chance of fog during a four hour ceremony. If fog is present during a four hour ceremony, there is a 61% chance that it will persist through the whole ceremony. Fog is much more likely to occur during the opening ceremonies than during the closing ceremonies. During the opening ceremonies, there is a better chance that precipitation will be snow vs. rain than during the closing ceremonies.	photo courtesy SLOC

Frequency of Various Weather Conditions Based on the CPC (Climate Prediction Center) Temperature Forecast Methodology

The statistics in this table represent the weighed average number of occurrences, out of a possible 504 hours, of various weather conditions from 5-25 February based on the past 30 years for the Salt Lake City International Airport. For example, when temperatures are above normal during this period dense fog is less frequent, therefore if the Olympic period is warmer than normal the frequency of dense fog would be less. Refer to the computation methodology and additional statistics for more information.

	20% Above	10% Above	Near Normal	10% Below	20% Below
Dense Fog - 1/4 Statute Mile or Less (without rain/snow):	6	8	10	12	14
Moderate or Heavy Snow:	4	4	4	4	4
Sustained Winds of 20 mph or Greater:	23	22	20	17	15
Wind Gusts of 40 mph or Greater:	2	2	2	2	2
Cloud Ceilings of 7000 Feet or Less:	42	47	52	56	61
Temperature at or Below Freezing (32 Degrees Farenheit):	167	181	203	210	238
Wet Bulb Temperature at or Below 28 Degrees Farenheit (without rain/snow):	120	136	151	166	181
Temperature at or Below 15 Degrees Farenheit:	8	11	14	17	20
Wind Chill Temperature at or Below 15 Degrees Farenheit:	59	68	76	85	94
Wind Shift of at Least 90 Degrees Between Consecutive Hours with Sustained Winds of at Least 8 Knots:	3	3	3	3	3
Frontal Passage Defined by Wind Shifts of at Least 90 Degrees Between Consecutive Hours with Sustained Winds of at Least 10 mph and a Pressure Jump of at Least 1.5 Millibars over 2 hours (from the hour before the wind shift to two hours afterwards):	1	1	1	1	1

Additional Climate Information for the Weather Forecast Team

Past Weather at Venues

Fog Climatology
Snow Climatology
Wind Climatology
Cloud Ceiling Climatology
Temperature/Wet Bulb/Wind Chill Climatology
Wind Shift Climatology
Frontal Passage Climatology

Means for February and March at Alta, Heber City, Pine View Dam, and Salt Lake City.

Geopotential Height Anomalies and Means for February and March

Anomalies	February	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001
	March	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001
Monthly Means	February	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001
	March	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001

1968-1996 Mean	February	March