Group 1 Mobile, Alabama Alana Smith Meredith Karr Charles Edwards Chris Swaim Lindsay Ash

Station ID: Mobile Regional Airport Latitude: 30° 41’ 29” Longitude: 88° 14’ 34” Elevation: 219 feet

Average Temperature

Average Temperature

Average Temperature Jan/Jul

Summer based on July temperatures Winter based on January temperatures Average mean temperatures changed little over the 58 years Summer temperatures stayed between 79° F and 84.6° F Winter temperatures stayed between 40.9° F and 64.6° F Variation occurred from one year to the next, but the trend lines show very little change occurred on average

Why might the average mean summer and winter temperatures in Mobile stay relatively constant? Mobile is adjacent to the Gulf of Mexico Oceans warm and cool more slowly than land Because water temperature does not change as quickly as air temperature, the temperature of nearby areas remain more constant Most landforms heat up relatively quickly during the day and cool down relatively quickly at night, which affects air temperature through the radiant heating and radiant cooling process. Yet, the ocean temperature counteracts these processes by not changing temperatures as quickly. Thus, large bodies of water moderate long-term temperature averages.

On average, the summer temperatures in Mobile are slightly higher than the summer temperatures in Alabama as a whole On average, the winter temperatures in Mobile are slightly higher than the winter temperatures in Alabama as a whole

Average mean summer and winter temperatures tend to be warmer in the southern parts of the state and cooler in the northern parts of the state Factors that may contribute to this: Continentality Latitude Altitude Why might Mobile’s average mean summer and winter temperatures be slightly higher than the rest of the state?

Continentality The ocean has a big influence on land areas near it (such as Mobile) So, if surrounded by land, the ocean doesn’t have as much influence (as is the case with most of Alabama) Thus, Alabama’s humid subtropical climate becomes more temperate with distance from the coast

Latitude Low latitudes (near the Equator, or 0º Latitude) see the most direct sunlight. Usually warmer Mobile has one of the lowest latitudes in the state High latitudes (near the poles, or 90º North or South Latitude), see the least amount of direct sunlight. Usually colder

Altitude Normally the the higher the elevation, the colder the temperature. Map shows that Mobile is one of the cities with the lowest elevation, making it warmer than many other places in Alabama

Although the average mean summer and winter temperatures vary from year to year, there is very little overall change during the 58 years observed because the Gulf of Mexico moderates the city’s long-term temperature averages. Summer and winter average mean temperatures tend to be warmer in Mobile than Alabama as a whole because of its close proximity to the Gulf of Mexico, lower latitude and lower elevation. Conclusions about Mobile’s Average Mean Summer and Winter Temperatures

Days over 90 o F and 85 o F Projected 3-7 degree rise in summer highs Temperature as part of heat index

Days over 90 o F

Summer Days over 90 o F

Past 20 Years

Days over 85 o F

Summer Days over 85 o F

Past 20 Years

Conclusions Overall Slight cooling Summer matches overall trend Increase in past 20 years Urban Heat Island?

Precipitation

Annual Precipitation

Difference of Precipitation from Year to Year

Years with a 10+ Fluctuation

Frost There are certain temperatures which, in one sense or another are recognized as being critical. One of these is the freezing point of water, or 32°F. The frost season is determined by the first and last dates of the year on which the minimum temperature stinks below 32°F.

In Mobile, the first frost of the year shows the trend of coming about 6 days later than it did in 1950, with the exception of the last 3 years.

In Mobile, the last frost of the year also shows the trend of getting later in the last 68 years. According to the slope, the last frost of the year occurs about 5 days later than it used to.

Why Frost matters?... Because it determines the length of the growing season. Mobile has one of the longest growing seasons in the United States.