SACKETT, C.J.

Defendant-appellant, Michael John Gilbert, appeals from jury verdict entered against him and in favor of plaintiff-appellee, Lester Jay Kirkpatrick, following an accident where defendant collided with plaintiff's disabled car stopped in the right lane of a two-lane road. The collision damaged plaintiff's car and injured plaintiff who had been standing in the roadway. Defendant, who had been driving in the left lane, argues he was forced into the right lane to avoid a collision with a van that, without signaling, suddenly swerved from the right to the left lane creating, he claims, a sudden emergency. Consequently he contends the district court erred in failing to instruct the jury on the legal excuse of sudden emergency. He also challenges the damage awards. We reverse and remand for a new trial.

I. BACKGROUND FACTS AND PROCEEDINGS.

The accident occurred at approximately 7:30 p.m. on October 1, 1999. Plaintiff's car had stalled in the right lane of southbound Highway 75, a controlled-access, divided, and curbed four-lane highway in that location. After plaintiff's car stalled, he stood in the right lane behind his car for a few minutes waving his arms in an attempt to alert the oncoming traffic to the presence of his car, a 1966 Ford Mustang that was not equipped with flashing hazard lights. It was dark and a rain-snow mix was beginning to fall. Defendant was driving southbound on Highway 75 in the left lane. Slightly ahead of defendant in the right lane was a dark-colored van. The van driver apparently did not immediately see plaintiff's stalled car in the right lane. Upon nearing a collision with plaintiff's stalled car, the van, without signaling, swerved into the left lane occupied by defendant. Defendant reacted to the van's swerving into his lane by braking and swerving into the right lane, to avoid a collision with the van. Having been shielded by the van, defendant was unaware that there was a stalled car in the right lane. The right front of defendant's car struck the left rear of plaintiff's stalled car. Seeing the approaching cars, plaintiff, who was standing in the road, jumped to get out of the way but was unable to get out of the road before the collision and was "clipped" by one of the cars. He was taken to the hospital and treated for lacerations and bruises and was released later that same evening.

Plaintiff sued, alleging defendant was negligent in the operation of his motor vehicle and as a result plaintiff was injured. At trial, defendant requested that a sudden emergency instruction be given. The district court refused to give the instruction and explained:

[T]he Court concludes that although unusual this is an emergency of the road that would be fairly routine or expected where there's a stalled vehicle on the highway. The key language the Court believes on the law of sudden emergency is that it's available to a driver who through no fault of his own is faced with a sudden emergency. Whether or not the defendant was at fault appears to be a fair question in this case; that here the defendant, following this van that was just a little bit ahead of him for ten seconds, and then suddenly changed lanes in front of the defendant, confronted with this situation, the defendant chose to change lanes quickly and blindly. Under these circumstances, a juror could find that that was negligent, but that there's an element of possible fault on behalf of the defendant that the Court believes precludes the use of the sudden emergency instruction.

The jury returned a verdict determining defendant to be sixty-nine percent at fault and plaintiff to be thirty-one percent at fault. The jury determined plaintiff was damaged in the total amount of $198,374.16. The award included $10,247 for past medical expenses, $40,202 for past pain and suffering, $97,925 for future pain and suffering, $2,500 for past loss of full mind and body, $2,500 for future loss of mind and body, $45,000 for loss of time-wages, and $0 for loss of future earning capacity. After making reductions for the fault of plaintiff, a judgment of $136,878.17 was entered in favor of plaintiff. The defendant made a motion for a new trial or remittitur which the district court denied.

II. REQUESTED INSTRUCTION.

Defendant's first contention is that the district court committed reversible error by refusing to give his requested sudden emergency jury instruction. We review the district court's determinations regarding jury instructions for correction of errors at law. Iowa R. App. P. 6.4; Beyer v. Todd, 601 N.W.2d 35, 38 (Iowa 1999). "As long as the requested instruction correctly states the law, has application to the case, and is not stated elsewhere in the instruction, the court must give the requested instruction." Id. (citing Vaughan v. Must, Inc., 542 N.W.2d 533, 539 (Iowa 1996)). If supported by the pleadings and substantial evidence in the record, parties are entitled to have their legal theories submitted to the jury. Id. "Evidence is substantial enough to support a requested instruction when a reasonable mind would accept it as adequate to reach a conclusion." Id. (citing Bride v. Heckart, 556 N.W.2d 449, 452 (Iowa 1996)). We view the evidence in the light most favorable to the party asserting a sudden emergency existed. Id. at 39. Nevertheless, failure to give a requested instruction does not warrant reversal unless it is prejudicial to the party requesting the instruction. Id. at 38.

The rule for what constitutes a sudden emergency is as follows: (1) an unforeseen combination of circumstances which calls for immediate action, (2) a perplexing contingency or complication of circumstances, and (3) a sudden or unexpected occasion for action, exigency, pressing necessity. Id. at 39.

The doctrine reflects the realization that a person who is confronted with an emergency situation is left no time for thought, or is reasonably so disturbed or excited, that he cannot weigh alternative courses of action, and must make a speedy decision, based largely upon impulse or guess. To excuse otherwise unlawful or negligent conduct, the event characterized as an emergency must compel if not an instantaneous response, certainly something fairly close to that.

Vasconez v. Mills, 651 N.W.2d 48, 54 (Iowa 2002) (internal quotation marks and citations omitted).

Defendant asserts that four factors worked together to cause a sudden emergency in this case: (1) the weather and corresponding lack of visibility, (2) plaintiff's stalled car in the highway, (3) the presence of plaintiff, himself, in the roadway, and (4) the van swerving into his lane.

Plaintiff argues that the weather conditions cannot be considered a sudden emergency in this case. We agree. Defendant admits that the poor weather conditions and their impact on visibility were not unforeseen. Where the peril created by the weather is not sudden and unexpected, it cannot be a factor in favor of issuing a jury instruction regarding sudden emergency. See id. at 54-55; see also Weiss v. Bal, 501 N.W.2d 478, 481 (Iowa 1993).

Defendant contends the van swerving into his lane of travel forcing him to take action and blocking his view of plaintiff's stalled and unlighted car in the right lane was a circumstance that required a jury instruction on sudden emergency. We view the evidence in the light most favorable to the party asserting a sudden emergency. Beyer, 601 N.W.2d at 39. We conclude the district court erred in failing to give a sudden emergency instruction. The circumstance of the van suddenly making an unsignaled lane change is not a routine traffic occurrence. The unsignaled lane change in this case is much like a defendant being suddenly confronted with a vehicle approaching in the wrong lane of traffic or a deer bounding into traffic, which are cases that require a sudden emergency instruction. Schmitt v. Jenkins Truck Lines, Inc., 170 N.W.2d 632, 645 (Iowa 1969); Mosell v. Estate of Marks, 526 N.W.2d 179, 182 (Iowa Ct.App. 1994). The unsignaled lane change in this case is similar, in that defendant claims an obstacle was suddenly and improperly impeding his path such that he would have had to either collide with the van or take some other sort of immediate action, such as what he did in this case — brake and swerve into a lane that he had no reason to believe was blocked by plaintiff's stalled car.

The present case is different than the case of a car suddenly stopping in front of a driver, where the sudden emergency instruction is not appropriate. Beyer, 601 N.W.2d at 39 ("A sudden stop in traffic on a divided four-lane highway, during a busy time of day . . . is not an uncommon or unforeseen event on the traveled roadways."). This is because a driver must maintain a reasonably safe distance between the cars ahead and maintain a speed that will permit the driver to bring the vehicle to a stop within an assured clear distance. Iowa Code §§ 321.285, .307 (2003); see also Beyer, 601 N.W.2d at 40. In the present case, taking the facts in the light most favorable to the defendant as we must, the van that caused defendant to brake and swerve was traveling in the lane next to defendant and made an unsignaled, illegal lane change that would have caused defendant to hit the van had he not braked and swerved. We determine this to be a combination of circumstances calling for immediate action by defendant. Thus, substantial evidence of a sudden emergency is present in this case and the district court should have given the requested instruction. Mosell, 526 N.W.2d at 182.

Furthermore, it was not for the district court to determine whether defendant was negligent in bringing on the sudden emergency. Whether a party is faced with a sudden emergency is ordinarily a question for the jury. Bangs v. Keifer, 174 N.W.2d 372, 374 (Iowa 1970). In this case, the determination of whether defendant was negligent should have been made by the jury following proper instruction on the applicable law. Therefore, we reverse and remand for a new trial.

Additionally, we find that failure to give the instruction did prejudice defendant. The jury instructions, as given, required the jury to find defendant negligent if it determined he broke any laws by his actions. An instruction on sudden emergency allows the jury to decide whether these actions are excused. The inability of the jury to consider that legal excuse did cause defendant prejudice.

Having determined that a new trial is required, we need not reach appellant's claim that the damage awards are flagrantly excessive and unsupported by the evidence.

REVERSED AND REMANDED WITH DIRECTIONS.