United States of America Climate

Climatic conditions are so diverse in the United States we have selected an example of states and detailed their individual climatic conditions in order to provide a more accurate climate overview.

FLORIDA

Summers throughout the state are long, warm, and fairly humid. Winters are mild with periodic invasions of cool to occasionally cold air. Coastal areas in all sections of Florida average slightly warmer temperatures in winter and cooler ones in summer.
The primary factors affecting the state's climate are latitude and numerous inland lakes. Proximity to the currents of the Atlantic Ocean and the Gulf of Mexico also plays an important role.
Florida is the thunderstorm capital of the United States. The "lightning belt" in Florida is an area from between Orlando and Tampa to south along the west coast to Fort Myers and east to Lake Okeechobee.
The thunderstorms generally occur during afternoons — June through September.
Florida is just subject to hurricane activity, the hurricane season officially runs from June 1 to November 30 each year.
Southern Florida is characterised by a tropical climate encompassing very warm weather year round and a minimal temperature range between seasons.

ALASKA

The climate varies widely throughout the state. Anchorage’s summer weather is pleasant and the winters are mild. Fairbanks, the Interior and parts of the Bush region experience Alaska’s most extreme weather conditions with average temperatures ranging from 22ºC in high summer to -28ºC in winter.

Generally, weather patterns ranging from Prince William Sound to Ketchikan are dominated primarily by low pressure systems creating  warm, moist, Pacific Ocean air over steep mountainous shoreline stretching throughout the area causing precipitation from upslope flow, temperature inversions and other surface based frictional effects.
During the winter months as the polar air mass moves Southward and strengthens with the jet stream, clear skies associated with high pressure centers located in Northwestern Canada may be seen frequently. The development of arctic air masses situated within the polar airmass establish frontal boundaries along steep temperature gradients which divide these air masses. Frontal activity associated with the pressure systems also plays a major role in weather development along the interior coastal areas of the Southeast. Cold stable air during the winter will generally cause widespread uniform precipitation and low level stratiform clouds.

NEW YORK STATE

New York has a  humid subtropical climate. Weather in New York is heavily influenced by two continental air masses: a warm, humid one from the southwest and a cold, dry one from the northwest.
The winters are long and cold in the Plateau Divisions of the state. In the majority of winter seasons, a temperature of −25 °C or lower can be expected in the northern highlands (Northern Plateau) and −15 °C or colder in the southwestern and east-central highlands (Southern Plateau).
The summer climate is cool in the Adirondacks, Catskills and higher elevations of the Southern Plateau. The New York City area and lower portions of the Hudson Valley have rather warm summers by comparison, with some periods of high, uncomfortable humidity. The remainder of New York State enjoys pleasantly warm summers, marred by only occasional, brief intervals of sultry conditions. Summer daytime temperatures usually range from the upper 19C to  25 to 30 °C, over much of the state.

SOUTH DAKOTA

South Dakota has a continental climate with four distinct seasons, ranging from very cold, dry winters to hot and semi-humid summers. During the summers, the average high temperature throughout the state is often close to 32 °C, although it generally cools down to near 15 °C at night. It is not unusual for South Dakota to have severe hot, dry spells in the summer with the temperature climbing above 38 °C several times every year. Winters are cold with January high temperatures averaging below freezing and low temperatures averaging below - 12 °C in most of the state.
Average annual rainfall in South Dakota ranges from semi-arid in the northwestern part of the state  381 mm to semi-humid around the southeast portion of the state 635 mm.

South Dakota summers bring frequent, sometimes severe, thunderstorms with high winds, thunder, and hail. The eastern part of the state is often considered part of Tornado Alley, and South Dakota experiences an average of 23 tornadoes per year. Winters are somewhat more stable, although severe weather in the form of blizzards and ice storms can occur during the season.

NEW MEXICO

The climate in New Mexico is varied based on changes in topographic features.  The State’s topography consists mainly of high plateaus or mesas, with numerous mountain ranges, canyons, valleys, and normally dry arroyos. 

New Mexico has a mild, arid or semiarid, continental climate characterized by light precipitation totals, abundant sunshine, low relative humidities, and a relatively large annual and diurnal temperature range.  The highest mountains have climate characteristics common to the Rocky Mountains.

Mean annual temperatures range from 18c in the extreme southeast to 40c in high mountains and valleys of the north. Elevation is a greater factor in determining the temperature of any specific locality than latitude.
 
During the summer months, individual daytime temperatures quite often exceed 40c at elevations below 5,000 feet, but the average monthly maximum temperatures during July, the warmest month, range from slightly above 30c at the lower elevations to the upper 23c at high elevations.  Warmest days quite often occur in June before the thunderstorm season sets in; during July and August. The average range between daily high and low temperatures is from 25o to 35o F.

In January, the coldest month, average daytime temperatures range form the middle 50s in the southern and central valleys to the middle 30s in the higher elevations of the north.  Minimum temperatures below freezing are common in all sections of the State during the winter, but subzero temperatures are rare except in the mountains. 

Rainfall– Average annual precipitation ranges from less than 10 inches over much of the southern desert and the Rio Grande and San Juan Valleys to more than 20 inches at higher elevations in the State.

CALIFORNIA

California climate varies from Mediterranean to subarctic. Much of the state has a Mediterranean climate, with cool, rainy winters and dry summers. The cool California Current offshore often creates summer fog near the coast. Further inland, one encounters colder winters and hotter summers.
Northern parts of the state average higher annual rainfall than the south. California's mountain ranges influence the climate as well: some of the rainiest parts of the state are west-facing mountain slopes. Northwestern California has a temperate climate, and the Central Valley has a Mediterranean climate but with greater temperature extremes than the coast. The high mountains, including the Sierra Nevada, have a mountain climate with snow in winter and mild to moderate heat in summer.
The east side of California's mountains has a drier rain shadow. The low deserts east of the southern California mountains experience hot summers and nearly frostless mild winters; the higher elevation deserts of eastern California see hot summers and cold winters.
On the coast, average yearly temperatures range between the low 4.4°C and in the high 21.1°C and 26.7°C. Farther inland, summers are hot and dry, and at higher altitudes the weather is more typical of a four-seasons cycle with cold, snowy winters.

HAWAII

The temperature ranges for Hawaii are
April- November: 75˚-88˚ F.
December- March: 68˚-80˚ F.
Average water temperature: 74˚ F.
The climate of Hawaiʻi is typical for a tropical area, although temperatures and humidity tend to be a bit less extreme due to the constant trade winds blowing from the east. Hawaii has only two seasons: summer from May to October, and winter from October to April. Local climates vary considerably on each island, grossly divisible into windward

TORNADO ALLEY

Although no state is entirely free of tornadoes, they are most frequent in the plains between the Rocky and Appalachian Mountains. The state where strong twisters most commonly occur is Oklahoma.
Florida has the highest density of tornado occurrence in the country. Nearly all of Florida's tornadoes are weak, short-lived. Oklahoma has the highest occurrence of such "classic" supercellular tornadoes. The most common definition of Tornado Alley is from northern Texas, northward through western Oklahoma and Kansas, and eastern Colorado and through Nebraska into south-eastern South Dakota, southern Minnesota and western Iowa.