SF340 flight crew rejected their takeoff for windshear.

Narrative

I was the First Officer; encountered gusty wind conditions and a possible wind shear event resulting in a rejected takeoff. On that evening I arrived at the aircraft earlier than usual because of darkening skies and inclement weather; which was approaching the area from the north. After I performed preflight duties and after the passengers were boarded; the flight blocked out slightly early in an effort to takeoff before the stormy weather arrived. As we taxied from the gate to the runway; the Captain and I noticed rising dust approximately 1/2 to 1 mile north of the field. We thought that we would be airborne and flying away from the worst of the weather before it arrived. An MD80 departed before us; and during its initial climb; I noticed that it did not weather vane; as much into the wind and that its exhaust was not carried downwind as quickly as I thought. I believed that was evidence of what to expect on our takeoff. The Tower Controller issued the wind condition; which was reported as a gusty crosswind; which was within the crosswind limitation of the aircraft. I noticed that the wind did not seem to be as strong as reported at our position; but I knew that could change any second. The Captain asked the Controller about reported windshear. There were no alerts for windshear. I asked the Captain if he were comfortable with the reported wind; and we agreed to attempt a takeoff. As I applied takeoff power (100% torque); the first strong gust hit the aircraft. I had to vigorously exercise the rudder pedals to maintain directional control and the centerline. The Captain asked if I had the aircraft under control and I replied that I did. I remained on the centerline; and as the airspeed increased to about 40-60 KTS the wind condition improved from a gusty crosswind to just a crosswind. However; as the airspeed increased beyond approximately 80 KTS; gusty winds resumed; and again I had to apply various degrees of rudder pressure to remain on centerline. I glanced down at the airspeed indicator for a fraction of a second just prior to V1; and I thought that we would be able to takeoff; but that it would likely be very turbulent on the initial climbout. I heard the captain call 'V1' and then; in almost the same breath; 'abort.' He reduced the power levers and; with a hand on his yoke; said 'my controls.' I released my yoke and said 'your aircraft.' As we slowed to exit the runway; I told the Tower Controller that we aborted our takeoff. The Controller asked if it was due of the weather; and I replied 'affirmative.' After completing required checklist items; we taxied back to the gate to have a high energy abort inspection completed. In my opinion; the Captain made a wise decision to call for the aborted takeoff. He; as the pilot monitoring; was able to note the airspeed trend. I did note the airspeed indicator (and other flight deck instruments) with series of quick glances; however; I was primarily looking straight ahead to maintain directional control. Since the Captain noticed the sudden; abnormal increase in airspeed (i.e. 40 KTS in a few seconds); he aborted the takeoff. Had we continued the takeoff; we may have lost up to 40 KTS of airspeed within a few seconds after becoming airborne.