Expectations

  • The first precursor of a incoming hurricane is the pre-hurricane squall line. The line resembles a line of showers and thunderstorms along a mid latitude cold front. Gusty winds accompany the showers and thunderstorms. The line is usually 100 to 200 miles ahead of the eye, but can be as much as 500 miles ahead of the eye in very large hurricanes.
  • The next part of a hurricane to affect the area are the outer convective bands. The typical hurricane has two or three of these bands (occasionally more in large hurricanes) which are comprised of cells resembling ordinary thunderstorms. These bands are in advance of the main rain shield. Wind gusts are higher in these bands than in the pre-hurricane squall line.
  • The rain shield is a solid or nearly solid area of rain that typically becomes heavier as the eye wall approaches. The wind, both sustained and peak gusts, keeps increasing as you move through the rain shield toward the storm's center or eye.
  • Another portion of the hurricane are the convective rings and bands. Also called spiral bands, when these pass through a location, the wind speed increases by as much as 50%, accompanied by a significant increase in the rainfall rate. When tornadoes and downbursts occur, they are likely to come from convective rings and bands.
  • Between convective bands, an area of stratiform rings and bands exist. Very light (if any) rain usually occurs while this area of the hurricane passes.
  • The eye wall will precede the hurricane's center. The eye wall is an organized band of convection that immediately surrounds the center. The fiercest winds and most intense rainfall typically occur near the eye wall.
  • Finally, the center of the hurricane or eye will pass over the area. The eye is usually a relatively calm center in the hurricane. The winds are light, the skies are partly cloudy or even clear and rain-free. The diameter of the eye can be as small as 5 miles or as large as 100 miles, averaging about 20 miles.